You should rely only on the information contained in this prospectus or in any free writing prospectus we may authorize to be delivered to you. Neither we nor the underwriters have authorized anyone to provide you with additional or different information. We and the underwriters are offering to sell, and seeking offers to buy, our common units only in jurisdictions where offers and sales are permitted. The information in this prospectus is accurate only as of the date of this prospectus, regardless of the time of delivery of this prospectus or any sale of our common units.

          Through and including                          , 2011 (25 days after the commencement of this offering), all dealers that effect transactions in our common units, whether or not participating in this offering, may be required to deliver a prospectus. This delivery requirement is in addition to a dealer's obligation to deliver a prospectus when acting as an underwriter and with respect to their unsold allotments or subscriptions.

          This prospectus contains forward-looking statements that are subject to a number of risks and uncertainties, many of which are beyond our control. See "Risk Factors" beginning on page 16 and "Forward-Looking Statements" beginning on page 179.

Industry and Market Data

          The market data and certain other statistical information used throughout this prospectus are based on independent industry publications, government publications or other published independent sources. Some data are also based on our good faith estimates. Although we believe these third-party sources are reliable and that the information is accurate and complete, we have not independently verified the information.

iv

Table of Contents

SUMMARY

          This summary highlights information contained elsewhere in this prospectus. You should read the entire prospectus carefully, including "Risk Factors" beginning on page 16 and the consolidated historical and pro forma financial statements and the related notes, before making an investment decision. The information presented in this prospectus assumes (i) an initial public offering price of $             per common unit and (ii) unless otherwise indicated, that the underwriters do not exercise their option to purchase additional common units from us.

          References in this prospectus to (i) "NGL Energy Partners LP," "we," "our," "us" or similar terms refer to NGL Energy Partners LP and its operating subsidiaries after giving effect to the formation transactions described in "— Formation Transactions and Partnership Structure," (ii) "NGL Energy Holdings LLC" or "general partner" refers to NGL Energy Holdings LLC, our general partner, (iii) "Silverthorne Operating LLC" or "operating company" refers to Silverthorne Operating LLC, the direct operating subsidiary of NGL Energy Partners LP, (iv) "NGL Supply Inc." or "NGL Supply" refers to NGL Supply, Inc., our predecessor for accounting purposes, (v) "Hicksgas" refers to the combined assets and operations of Hicksgas Gifford, Inc., which we refer to as Gifford, and Hicksgas, LLC, which we refer to as Hicks LLC and (vi) the "NGL Energy Investor Group" refers to, collectively, the NGL Energy GP Investor Group and the NGL Energy LP Investor Group, as defined on pages 4 and 5.

Our Company

Overview

          We are a Delaware limited partnership formed in September 2010 to own and operate a vertically-integrated propane business with three operating segments: retail propane; wholesale supply and marketing; and midstream. We engage in the following activities through our operating segments:

•

our retail propane business sells propane to end users consisting of residential, agricultural, commercial and industrial customers;



•

our wholesale supply and marketing business supplies propane and other natural gas liquids and provides related storage to retailers, wholesalers and refiners; and



•

our midstream business, which currently consists of our propane terminaling business, takes delivery of propane from pipelines or trucks at our propane terminals and transfers the propane to third-party transport trucks for delivery to retailers, wholesalers or other consumers.

Our Assets and Areas of Operation

          Retail Propane.    Our retail propane business consists of the retail marketing, sale and distribution of propane, including the sale and lease of propane tanks, equipment and supplies, to more than 56,000 residential, agricultural, commercial and industrial customers. Based on industry statistics from LPGas magazine, we believe that we are the 12th largest domestic retail propane distribution company by volume.

          We market retail propane primarily in Georgia, Illinois, Indiana and Kansas through our customer service locations. We own or lease 44 customer service locations and 37 satellite distribution locations, with aggregate above-ground propane storage capacity of approximately four million gallons. We also own a fleet of bulk delivery trucks and service vehicles.

          Wholesale Supply and Marketing.    Our wholesale supply and marketing business provides propane procurement, storage, transportation and supply services to customers through assets owned by us and by third parties. Our wholesale supply and marketing business also obtains the majority of the propane supply for our retail propane business.

1

Table of Contents

          We procure propane from refiners, gas processing plants, producers and other resellers for delivery to leased storage, common carrier pipelines, rail car terminals and direct to certain customers. From September 15 through March 15 each year, we have the right to utilize 100% of the current capacity on the ConocoPhillips Blue Line pipeline, which runs from Borger, Texas to our propane terminals in East St. Louis, Illinois and Jefferson City, Missouri. We lease approximately 67 million gallons of propane storage space in various strategic locations to accommodate the supply requirements and contractual needs of our retail and wholesale customers.

          Midstream.    Our midstream business, which currently consists of our propane terminaling business, takes delivery of propane from a pipeline or truck at our propane terminals and transfers the propane to third party trucks for delivery to propane retailers, wholesalers or other customers. Our midstream assets consist of our three state-of-the-art propane terminals in East St. Louis, Illinois; Jefferson City, Missouri; and St. Catharines, Ontario. We are the exclusive service provider at each of our terminals, which have a combined annual throughput in excess of 170 million gallons of propane.

Our Business Strategies

          Our principal business objective is to increase the quarterly distributions that we pay to our unitholders over time while ensuring the ongoing stability of our business. We expect to achieve this objective by executing the following strategies:

•

grow through strategic acquisitions;



•

pursue organic growth;



•

focus on consistent annual cash flows; and



•

maintain a disciplined capital structure.

Our Competitive Strengths

          We believe that we are well-positioned to successfully execute our business strategies and achieve our principal business objective because of the following competitive strengths:

•

our experienced management team with extensive acquisition and integration experience;



•

cash flows from our vertically integrated and diversified operations;



•

our high percentage of retail sales to residential customers;



•

our wholesale supply and marketing business; and



•

our propane terminals and capacity on the Blue Line pipeline.

Risk Factors

          An investment in our common units involves risks associated with our business, our partnership structure and the tax characteristics of our common units. Please read "Risk Factors" beginning on page 16 carefully for a discussion of these risks.

2

Table of Contents

Formation Transactions and Partnership Structure

          We are a Delaware limited partnership formed in September 2010 to own and, through our subsidiaries, operate the propane and other natural gas liquids businesses that historically were owned and operated by NGL Supply and Hicksgas. In October 2010, the following transactions, which we refer to as the formation transactions, occurred:

•

Hicks Oils & Hicksgas, Incorporated, or HOH, formed a wholly owned subsidiary, Hicks LLC, and contributed to it all of HOH's propane and propane-related assets. The shareholders of Gifford contributed all of their shares of stock in Gifford to a newly formed holding company, Gifford Holdings, Inc.



•

Each of the NGL Supply Parties, the Coady Parties and the IEP Parties, as those terms are defined by the listings in the table below, made capital contributions to our general partner in exchange for membership interests in our general partner in the aggregate amounts of 36.47%, 31.00% and 32.53%, respectively.



•

Our general partner made a cash capital contribution of approximately $58,800 to us in exchange for the continuation of its 0.1% general partner interest in us and incentive distribution rights and the IEP Parties made a cash capital contribution to us in the aggregate amount of approximately $11.0 million in exchange for an aggregate 18.67% limited partner interest in us.



•

NGL Supply and Gifford each converted into a limited liability company and the members of NGL Supply, Hicks LLC and Gifford contributed 100% of their respective membership interests in those entities to us as capital contributions in exchange for (i) in the case of NGL Supply, a 43.27% limited partner interest in us, a cash distribution of approximately $40.0 million and our agreement to pay or cause to be paid approximately $27.9 million of existing indebtedness of NGL Supply, (ii) in the case of Hicks LLC, a 37.96% limited partner interest in us, a cash distribution of approximately $1.6 million and our agreement to pay or cause to be paid approximately $6.5 million of existing indebtedness of Hicks LLC and (iii) in the case of Gifford, a cash payment of approximately $15.5 million.



•

We made a capital contribution of 100% of the membership interests of each of NGL Supply, Hicks LLC and Gifford to our wholly owned operating subsidiary, Silverthorne Operating LLC.

          On October 14, 2010, we entered into a $150 million revolving credit facility, consisting of a $50 million working capital facility and a $100 million acquisition facility, with a group of lenders. In February 2011, we increased the committed amount under the acquisition facility to $130 million, which increased our total revolving credit facility capacity to $180 million.

3

Table of Contents

          As of January 31, 2011, the following individuals and entities, which we collectively refer to as the NGL Energy GP Investor Group, owned all of the outstanding membership interests in our general partner in the percentages set forth below:

4

Table of Contents

          As of January 31, 2011, the following individuals and entities, which we collectively refer to as the NGL Energy LP Investor Group, owned all of our outstanding common units in the percentages set forth below:

          At the completion of this offering, each common unit held by the members of the NGL Energy LP Investor Group will split into             common units and              common units held by the NGL Energy LP Investor Group will be converted on a pro rata basis into             subordinated units.

5

Table of Contents

Ownership and Organizational Structure

          The following table sets forth our organization and ownership based on total units outstanding after the completion of this offering, the split of each common unit held by the members of the NGL Energy LP Investor Group into             common units and the conversion of             common units held by the NGL Energy LP Investor Group into             subordinated units.

          As is common with publicly traded partnerships, in order to maintain operational flexibility we will conduct our operations through subsidiaries. Our one direct subsidiary, Silverthorne Operating LLC, is a Delaware limited liability company that will conduct business itself and through its subsidiaries. The following diagram depicts our organizational and ownership structure after the completion of this offering, the split of each common unit held by the members of the NGL Energy LP Investor Group into             common units and the conversion of              common units held by the NGL Energy LP Investor Group into             subordinated units.

6

Table of Contents

Our Management

          Our general partner has sole responsibility for conducting our business and for managing our operations and will be owned and controlled by the NGL Energy GP Investor Group. Our general partner will make decisions on our behalf through its board of directors and executive officers, which executive officers are also officers of our operating company. We will reimburse our general partner and its affiliates for all expenses they incur or payments they make on our behalf. Our partnership agreement provides that our general partner will determine in good faith the expenses that are allocable to us.

          Upon the completion of this offering, the board of directors of our general partner will have four members. Our general partner intends to increase the size of the board to six members within 12 months following the completion of this offering. Neither our general partner nor its board of directors will be elected by our unitholders. The NGL Energy GP Investor Group will have the right to appoint our general partner's entire board of directors, including the independent directors.

Summary of Conflicts of Interest and Fiduciary Duties

          Our general partner has a legal duty to manage us in a manner beneficial to our partners. This legal duty originates in statutes and judicial decisions and is commonly referred to as a "fiduciary duty." At the same time, the officers and directors of our general partner also have fiduciary duties to manage our general partner in a manner beneficial to its owners. As a result, conflicts of interest may arise in the future between us and the holders of our common units, on the one hand, and our general partner and its affiliates on the other hand. For example, our general partner will be entitled to make determinations that affect the amount of cash distributions we make to the holders of common and subordinated units, which in turn has an effect on whether our general partner receives incentive distributions, as described in "— The Offering."

          Our partnership agreement limits the liability of and reduces the fiduciary duties owed by our general partner to holders of our common units. Our partnership agreement also restricts the remedies available to holders of our common units for actions that might otherwise constitute a breach of our general partner's fiduciary duties. By purchasing a common unit, the purchaser agrees to be bound by the terms of our partnership agreement, and pursuant to the terms of our partnership agreement each holder of common units consents to various actions and potential conflicts of interest contemplated in the partnership agreement that might otherwise be considered a breach of fiduciary or other duties under applicable state law.

          For a more detailed description of the conflicts of interest and the fiduciary duties of our general partner, please read "Conflicts of Interest and Fiduciary Duties."

Principal Executive Offices and Internet Address

          Our principal executive offices are located at 6120 South Yale Avenue, Suite 805, Tulsa, Oklahoma 74136. Our telephone number is (918) 481-1119. We expect our website to be located at www.nglenergypartners.com following the completion of this offering. We expect to make available our periodic reports and other information filed with or furnished to the SEC free of charge through our website, as soon as reasonably practicable after those reports and other information are electronically filed with or furnished to the SEC. Information on our website or any other website is not incorporated by reference into this prospectus and does not constitute a part of this prospectus.

7

Table of Contents

The Offering

8

Table of Contents

9

Table of Contents

10

Table of Contents

11

Table of Contents

12

Table of Contents

Summary Historical and Unaudited Pro Forma Financial and Operating Data

          We were formed on September 8, 2010, and we do not have our own historical financial statements for periods prior to our formation. The following table shows summary historical financial and operating data for NGL Supply, our predecessor for accounting purposes, and pro forma financial and operating data for NGL Energy Partners LP for the periods and as of the dates presented. The following table should be read in conjunction with "Selected Historical and Unaudited Pro Forma Financial and Operating Data" and the accompanying financial statements and related notes included elsewhere in this prospectus.

          The summary historical financial data as of March 31, 2010 and 2009 and for the fiscal years ended March 31, 2010, 2009 and 2008 are derived from the audited historical consolidated financial statements of NGL Supply included elsewhere in this prospectus. The summary historical financial data as of September 30, 2010 and for the six months ended September 30, 2010 and 2009 are derived from the unaudited historical consolidated financial statements of NGL Supply included elsewhere in this prospectus and NGL Supply's financial records. The results of operations for the interim periods are not necessarily indicative of operating results for the entire year or any future period.

          Our summary unaudited pro forma financial data as of September 30, 2010 and for the fiscal year ended March 31, 2010 and the six months ended September 30, 2010 are derived from the unaudited pro forma financial statements of NGL Energy Partners LP included elsewhere in this prospectus. The pro forma adjustments have been prepared as if the following transactions had taken place on September 30, 2010, in the case of the unaudited pro forma balance sheet, and as of April 1, 2009, in the case of the unaudited pro forma statement of operations:

•

the formation transactions;



•

the split of each common unit held by the members of the NGL Energy LP Investor Group into                 common units;



•

the application of the net proceeds from this offering as described in "Use of Proceeds;" and



•

the entry into our revolving credit facility.

          The pro forma financial and operating data does not give effect to approximately $1.0 million of estimated incremental annual administration expenses we expect to incur as a result of being a publicly traded partnership.

          The following table includes historical EBITDA and Adjusted EBITDA for NGL Supply and our pro forma EBITDA and Adjusted EBITDA, which have not been prepared in accordance with generally accepted accounting principles, or GAAP. These measures are presented because they are helpful to management, industry analysts, investors, lenders and rating agencies and may be used to assess the financial performance and operating results of our fundamental business activities. For definitions of EBITDA and Adjusted EBITDA and a reconciliation of EBITDA and Adjusted EBITDA to their most

13

Table of Contents

directly comparable financial measure calculated and presented in accordance with GAAP, please read " — Non-GAAP Financial Measures" below.

(1)

The acquisition of retail propane businesses by NGL Supply in fiscal years 2008 through 2010 affects the comparability of this information.

(2)

Capital expenditures for improvement of existing capital assets.

(3)

Capital expenditures for expansion of our operating capacity or operating income.

(4)

Includes intercompany volumes sold to our retail propane segment.

14

Table of Contents

Non-GAAP Financial Measures

          We define EBITDA as net income (loss) attributable to parent entity plus income taxes, interest expense and depreciation and amortization expense. Management believes it is appropriate to exclude certain items from EBITDA because management believes these items affect the comparability of operating results. We define Adjusted EBITDA as EBITDA excluding the unrealized gain or loss on derivative contracts, the gain or loss on the disposal of assets and share-based compensation expenses. EBITDA and Adjusted EBITDA are non-GAAP financial measures that management and external users of our consolidated financial statements, such as industry analysts, investors, lenders and rating agencies, may use to assess:

•

our operating performance as compared to other publicly traded partnerships in the propane industry, without regard to capital structure, historical cost basis or financing methods;



•

our ability to incur and service debt and fund capital expenditures;



•

the ability of our assets to generate sufficient cash flow to make distributions to our unitholders; and



•

the viability of acquisitions and other capital expenditure projects and the returns on investment of various investment opportunities.

          We believe that the presentation of EBITDA and Adjusted EBITDA in this prospectus provides information useful to investors in assessing our financial condition and results of operations. The GAAP measure most directly comparable to EBITDA and Adjusted EBITDA is net income. Our non-GAAP financial measures of EBITDA and Adjusted EBITDA should not be considered as an alternative to GAAP net income. EBITDA and Adjusted EBITDA have important limitations as analytical tools because they exclude some but not all items that affect net income. You should not consider EBITDA and Adjusted EBITDA in isolation or as a substitute for analysis of our results as reported under GAAP. Because EBITDA and Adjusted EBITDA may be defined differently by other companies in our industry, our definitions of EBITDA and Adjusted EBITDA may not be comparable to similarly titled measures of other companies, thereby diminishing their utility.

          The following table presents a reconciliation of the non-GAAP financial measures of EBITDA and Adjusted EBITDA to the GAAP financial measure of net income on a historical and pro forma basis:

15

Table of Contents

RISK FACTORS

          Limited partner units are inherently different from capital stock of a corporation, although many of the business risks to which we are subject are similar to those that would be faced by a corporation engaged in similar businesses. We urge you to consider carefully the following risk factors together with all of the other information included in this prospectus in evaluating an investment in our common units.

          If any of the following risks were to occur, our business, financial condition or results of operations could be materially adversely affected. In that case, we might be unable to pay the minimum quarterly distribution on our common units, the trading price of our common units could decline and you could lose all or part of your investment in us.

Risks Related to Our Business

We may not have sufficient cash to enable us to pay the minimum quarterly distribution to our unitholders following the establishment of cash reserves by our general partner and the payment of costs and expenses, including reimbursement of expenses to our general partner.

          We may not have sufficient cash each quarter to enable us to pay the minimum quarterly distribution. The amount of cash we can distribute on our common and subordinated units principally depends on the amount of cash we generate from our operations, which will fluctuate from quarter to quarter based on, among other things:

•

weather conditions in our operating areas;



•

the cost of propane that we buy for resale and whether we are able to pass along cost increases to our customers;



•

the volume of propane throughput in our terminals;



•

disruptions in the availability of propane supply;



•

the level of competition from other propane companies and other energy providers; and



•

prevailing economic conditions.

          In addition, the actual amount of cash we will have available for distribution also depends on other factors, some of which are beyond our control, including:

•

the level of capital expenditures we make;



•

the cost of acquisitions, if any;



•

restrictions contained in our revolving credit facility and other debt service requirements;



•

fluctuations in working capital needs;



•

our ability to borrow funds and access capital markets;



•

the amount, if any, of cash reserves established by our general partner; and



•

other business risks discussed in this prospectus that potentially affect our cash levels.

Because of all these factors, we may not have sufficient available cash each quarter to be able to pay the minimum quarterly distribution.

          For a description of additional restrictions and factors that may affect our ability to make cash distributions, please read "Our Cash Distribution Policy and Restrictions On Distributions."

16

Table of Contents

The amount of cash we have available for distribution to our unitholders depends primarily on our cash flow rather than on our profitability, which may prevent us from making distributions, even during periods in which we realize net income.

          The amount of cash we have available for distribution depends primarily on our cash flow and not solely on profitability, which will be affected by non-cash items. As a result, we may make cash distributions during periods when we record net losses for financial accounting purposes and may not make cash distributions during periods when we record net income for financial accounting purposes.

On a pro forma basis we would not have had sufficient cash available for distribution to pay the full minimum quarterly distribution on all subordinated units for the fiscal year ended March 31, 2010 or the twelve months ended September 30, 2010.

          The amount of pro forma cash available for distribution generated during the fiscal year ended March 31, 2010 and the twelve months ended September 30, 2010 would have been sufficient to allow us to pay the full minimum quarterly distribution on all of our common units, but only approximately         % and          %, respectively, of the full minimum quarterly distribution on our subordinated units during those periods. For a calculation of our ability to make cash distributions to our unitholders based on our pro forma results for the fiscal year ended March 31, 2010 and the twelve months ended September 30, 2010, please read "Our Cash Distribution Policy and Restrictions on Distributions."

The assumptions that we make in the computation of our forecast of cash available for distribution included in "Our Cash Distribution Policy and Restrictions on Distributions" are inherently uncertain and are subject to significant business, economic, financial, regulatory and competitive risks and uncertainties, including weather conditions, that could cause actual results to differ materially from our forecasted results.

          The forecast of cash available for distribution in "Our Cash Distribution Policy and Restrictions on Distributions" includes our forecasted results of operations, Adjusted EBITDA and cash available for distribution for the twelve months ending June 30, 2012. We prepared the financial forecast, and we have not received an opinion or report on such forecast from our or any other independent auditor. The assumptions underlying the forecast are inherently uncertain and are subject to significant business, economic, financial, regulatory and competitive risks and uncertainties, including weather conditions, that could cause actual results to differ materially from those forecasted. If we do not achieve the forecasted results, we may be unable to pay the full minimum quarterly distribution or any amount on our common units or subordinated units, in which event the market price of our common units may decline materially.

Current conditions in the global capital and credit markets, and general economic pressures, may adversely affect our financial position and results of operations.

          Our business and operating results are materially affected by worldwide economic conditions. Current conditions in the global capital and credit markets and general economic pressures have led to declining consumer and business confidence, increased market volatility and widespread reduction of business activity generally. As a result of this turmoil, coupled with increasing energy prices, our customers may experience cash flow shortages which may lead to delayed or cancelled plans to purchase our products, and affect the ability of our customers to pay for our products. In addition, disruptions in the U.S. residential mortgage market, increases in mortgage foreclosure rates and failures of lending institutions may adversely affect retail customer demand for our products (in particular, products used for home heating and home comfort equipment) and our business and results of operations.

17

Table of Contents

Our retail propane operations are concentrated in the Midwest and Southeast, and localized warmer weather and/or economic downturns may adversely affect demand for propane in those regions, thereby affecting our financial condition and results of operations.

          A substantial portion of our retail propane sales are to residential customers located in the Midwest and Southeast who rely heavily on propane for heating purposes. On a combined pro forma basis for the fiscal year ended March 31, 2010, approximately 79% of our retail propane volume was attributable to sales during the peak heating season of October through March. Warmer weather may result in reduced sales volumes that could adversely impact our operating results and financial condition. In addition, adverse economic conditions in areas where our retail propane operations are concentrated may cause our residential customers to reduce their use of propane regardless of weather conditions. Localized warmer weather and/or economic downturns may have a significantly greater impact on our operating results and financial condition than if our retail propane business were less concentrated.

Widely fluctuating propane prices could adversely affect our ability to finance our working capital needs.

          The price for propane is subject to wide fluctuations and depends on numerous factors beyond our control. If propane prices were to increase substantially, our working capital needs would increase to the extent that we are required to maintain propane inventory that has not been pre-sold and our ability to finance our working capital could be adversely affected. If propane prices were to decline significantly for a prolonged period, the decreased value of our propane inventory could potentially result in a reduction of the borrowing base under our working capital credit facility and we could be required to liquidate propane inventory that we have already pre-sold.

We have certain agreements with ConocoPhillips related to the operation and maintenance of two of our propane terminals, our propane supply, the lease of a propane storage facility in Borger, Texas and the ability to access the Blue Line pipeline of ConocoPhillips. The termination of, or significant modification to, these agreements could have a negative impact on our financial condition and results of operations.

          In connection with the purchase by NGL Supply of the propane terminals of ConocoPhillips in November 2002, we executed several agreements, including the following:

•

an operating and maintenance agreement for the propane terminals and common facilities located in Missouri and Illinois;



•

a propane supply agreement under which we are able to purchase, exchange and deliver specified gallons of propane per week and access the ConocoPhillips Blue Line pipeline to ship propane from Borger, Texas and the Conway, Kansas storage hubs to our propane terminal locations in Missouri and Illinois, including full dedicated capacity of such pipeline during the period of September 15 through March 15; and



•

a propane storage lease agreement under which we have leased storage space of approximately 36 million gallons in Borger, Texas.

          The operating and maintenance agreement and the propane supply agreement each expire in November 2012 and provide for a five-year extension period at our option followed by a year-to-year continuation. The propane storage lease agreement expires in 2012, and we are in discussions with ConocoPhillips regarding the extension of this agreement. Significant changes to such agreements or our inability to extend such agreements could have a negative effect on our financial condition and results of operations.

18

Table of Contents

If we do not successfully identify acquisition candidates, complete accretive acquisitions on economically acceptable terms or adequately integrate the acquired operations into our existing operations, our future financial performance may be adversely affected and our growth may be limited.

          A focus of our principal business objective is to increase the cash distributions on our units by expanding our business in each of our operating segments. There can be no assurance that we will identify attractive acquisition candidates in the future, that we will be able to acquire such businesses on economically acceptable terms, that any acquisitions will not be dilutive to earnings and distributions or that any additional debt that we incur to finance an acquisition will not affect our ability to make distributions to unitholders. We may also be subject to certain covenants in our revolving credit facility that may restrict our ability to incur indebtedness to finance acquisitions. In addition, any new debt we incur to finance acquisitions may adversely affect our ability to make distributions to our unitholders.

          The propane industry is a mature industry. We anticipate only limited growth in total national demand for propane in the near future. Increased competition from alternative energy sources has limited growth in the propane industry, and year-to-year industry volumes are primarily impacted by fluctuations in weather and economic conditions. In addition, our retail propane business concentrates on sales to residential customers, but because of longstanding customer relationships that are typical in the retail residential propane industry, the inconvenience of switching tanks and suppliers and propane's generally higher cost as compared to certain other energy sources, we may have difficulty in increasing our retail customer base other than through acquisitions. Therefore, while our business strategy includes expanding our existing operations through internal growth, our ability to grow within the industry will depend principally on acquisitions.

          Our future financial performance depends on our ability to make acquisitions at economical prices. However, we may be unable to grow as rapidly as we expect through acquiring additional businesses after the completion of this offering for various reasons, including the following:

•

we will use our cash from operations primarily for reinvestment in our business and distributions to unitholders. The extent to which we are unable to use cash or access capital to pay for additional acquisitions may limit our growth and impair operating results.



•

due to the consolidation that has occurred in the retail propane industry, competition for acquisitions has intensified, making it more difficult to acquire businesses on economically acceptable terms.



•

although we intend to use common units as an acquisition currency, some prospective sellers may be unwilling to accept units as consideration and their issuance in some circumstances may be dilutive to our existing unitholders.

          Moreover, acquisitions involve potential risks, including:

•

the inability to integrate the operations of recently acquired businesses;



•

the assumption of unknown liabilities;



•

limitations on rights to indemnity from the seller;



•

mistaken assumptions about the overall costs of equity or debt or synergies;



•

unforeseen difficulties operating in new geographic areas;



•

the diversion of management's and employees' attention from other business concerns;



•

customer or key employee loss from the acquired businesses; and



•

a significant increase in our indebtedness and related interest expense.

19

Table of Contents

          If we consummate any future acquisitions, our capitalization and results of operations may change significantly, and unitholders will not have the opportunity to evaluate the economic, financial and other relevant information that we will consider in determining the application of these funds and other resources.

Part of our growth strategy includes acquiring businesses with operations that may be distinct and separate from our existing operations, which could subject us to additional business and operating risks.

          We may expand our operations into businesses that differ from our existing operations, such as the natural gas midstream business (including, but not limited to, natural gas gathering, processing and transportation). Integration of new businesses is a complex, costly and time-consuming process and may involve assets with which we have limited operating experience. Failure to timely and successfully integrate acquired businesses into our existing operations may have a material adverse effect on our business, financial condition or results of operations. The difficulties of integrating new businesses into our existing operations include, among other things: operating distinct businesses that require different operating strategies and different managerial expertise; the necessity of coordinating organizations, systems and facilities in different locations; integrating personnel with diverse business backgrounds and organizational cultures; and consolidating corporate and administrative functions. In addition, the diversion of our attention and any delays or difficulties encountered in connection with the integration of the new businesses, such as unanticipated liabilities or costs, could harm our existing business, results of operations, financial condition or prospects. Furthermore, new businesses will subject us to additional business and operating risks such as the acquisitions not being accretive to our unitholders as a result of decreased profitability, increased interest expense related to debt we incur to make such acquisitions or an inability to successfully integrate those operations into our overall business operation. The realization of any of these risks could have a material adverse effect on our financial condition or results of operations.

Debt we incur in the future may limit our flexibility to obtain financing and to pursue other business opportunities.

          Our future level of debt could have important consequences to us, including the following:

•

our ability to obtain additional financing, if necessary, for working capital, capital expenditures, acquisitions or other purposes may be impaired or such financing may not be available on favorable terms;



•

our funds available for operations, future business opportunities and distributions to unitholders will be reduced by that portion of our cash flow required to make principal and interest payments on our debt;



•

we may be more vulnerable to competitive pressures or a downturn in our business or the economy generally; and



•

our flexibility in responding to changing business and economic conditions may be limited.

          Our ability to service our debt will depend on, among other things, our future financial and operating performance, which will be affected by prevailing economic and weather conditions and financial, business, regulatory and other factors, some of which are beyond our control. If our operating results are not sufficient to service our future indebtedness, we will be forced to take actions such as reducing distributions, reducing or delaying our business activities, acquisitions, investments or capital expenditures, selling assets or seeking additional equity capital. We may be unable to effect any of these actions on satisfactory terms or at all.

20

Table of Contents

Restrictions in our revolving credit facility could adversely affect our business, financial condition, results of operations, ability to make distributions to unitholders and the value of our common units.

          Our revolving credit facility limits our ability to, among other things:

•

incur additional debt or letters of credit;



•

make distributions on or redeem or repurchase units;



•

make certain loans, investments and acquisitions;



•

incur certain liens or permit them to exist;



•

engage in sale and leaseback transactions;



•

prepay, redeem or purchase certain indebtedness;



•

enter into certain types of transactions with affiliates;



•

enter into agreements limiting subsidiary distributions;



•

change the nature of our business or enter into a substantially different business;



•

merge or consolidate with another company; and



•

transfer or otherwise dispose of assets.

          Our revolving credit facility also contains covenants requiring us to maintain certain financial ratios. Please read "Management's Discussion and Analysis of Financial Condition and Results of Operations — Liquidity, Sources of Capital and Capital Resource Activities."

          The provisions of our revolving credit facility may affect our ability to obtain future financing and pursue attractive business opportunities and our flexibility in planning for, and reacting to, changes in business conditions. In addition, a failure to comply with the provisions of our revolving credit facility could result in a covenant violation, default or an event of default that could enable our lenders, subject to the terms and conditions of our revolving credit facility, to declare the outstanding principal of that debt, together with accrued and unpaid interest, to be immediately due and payable. If we were unable to repay the accelerated amounts, our lenders could proceed against the collateral we granted them to secure our debts. If the payment of our debt is accelerated, defaults under our other debt instruments, if any then exist, may be triggered, and our assets may be insufficient to repay such debt in full, and our unitholders could experience a partial or total loss of their investment.

Increases in interest rates could adversely impact our unit price, our ability to issue equity or incur debt for acquisitions or other purposes, and our ability to make cash distributions at our intended levels.

          Interest rates may increase in the future. As a result, interest rates on our existing and future credit facilities and debt offerings could be higher than current levels, causing our financing costs to increase accordingly. As with other yield-oriented securities, our unit price will be impacted by our level of cash distributions and implied distribution yield. The distribution yield is often used by investors to compare and rank yield-oriented securities for investment decision-making purposes. Therefore, changes in interest rates, either positive or negative, may affect the yield requirements of investors who invest in our units, and a rising interest rate environment could have an adverse impact on our unit price and our ability to issue equity or incur debt for acquisitions or other purposes and to make cash distributions at our intended levels.

21

Table of Contents

Our results of operations could be negatively impacted by price and inventory risk related to our business and management of these risks.

          Generally, we attempt to maintain an inventory position that is substantially balanced between our purchases and sales, including our future delivery obligations. We attempt to obtain a certain gross margin for our propane purchases by selling our propane to our wholesale and retail market customers which include third-party consumers, other wholesalers and retailers, and others. Our strategy may be ineffective in limiting our price and inventory risks if, for example, market, weather or other conditions prevent or allocate the delivery of physical product during periods of peak demand. If the market price falls below the cost at which we made such purchases, it could adversely affect our profits. Any event that disrupts our expected supply of propane could expose us to a risk of loss through price changes if we were required to obtain supply at increased prices that cannot be passed through to our customers. While we attempt to balance our inventory position through our normal risk management policies and practices, it is not possible to eliminate all price risks.

Our risk management policies cannot eliminate all risks. In addition, any non-compliance with our risk management policies could result in significant financial losses.

          Although we have risk management policies and systems that are intended to quantify and manage risk, some degree of exposure to unforeseen fluctuations in market conditions remains. In addition, our wholesale operations involve a level of risk from non-compliance with our stated risk management policies. We monitor processes and procedures to prevent unauthorized trading and to maintain substantial balance between purchases and future sales and delivery obligations. However, we cannot assure you that our processes will detect and prevent all violations of our risk management policies, particularly if such violation involves deception or other intentional misconduct. There is no assurance that our risk management procedures will prevent losses that would negatively affect our business, financial condition and results of operations.

The counterparties to our commodity derivative and physical purchase and sale contracts may not be able to perform their obligations to us, which could materially affect our cash flows and results of operations.

          We encounter risk of counterparty non-performance primarily in our wholesale supply and marketing business. Disruptions in the supply of propane and in the oil and gas commodities sector overall for an extended or near term period of time could result in counterparty defaults on our derivative and physical purchase and sale contracts. This could impair our ability to obtain supply to fulfill our sales delivery commitments or obtain supply at reasonable prices, which could result in decreased gross margins and profitability, thereby impairing our ability to make distributions to our unitholders.

Our use of derivative financial instruments could have an adverse effect on our results of operations.

          We have used derivative financial instruments as a means to protect against commodity price risk or interest rate risk and expect to continue to do so. We may, as a component of our overall business strategy, increase or decrease from time to time our use of such derivative financial instruments in the future. Our use of such derivative financial instruments could cause us to forego the economic benefits we would otherwise realize if commodity prices or interest rates were to change in our favor. In addition, although we monitor such activities in our risk management processes and procedures, such activities could result in losses, which could adversely affect our results of operations and impair our ability to make distributions to our unitholders.

22

Table of Contents

If the price of propane increases suddenly and sharply, we may be unable to pass on the increase to our retail customers and our retail customers may conserve their propane use or convert to alternative energy sources, thereby adversely affecting our profit margins.

          The propane industry is a "margin-based" business in which our realized gross margins depend on the differential of sales prices over our total supply costs. Our profitability is therefore sensitive to changes in the wholesale prices of propane caused by changes in supply or other market conditions. The timing of cost increases by our propane suppliers can significantly affect our gross margins because we may be unable to immediately pass through rapid increases in the wholesale costs of propane to our retail customers, if at all. We have no control over supply or market conditions. In general, product supply contracts permit suppliers to charge posted prices at the time of delivery or the current prices established at major storage points. Sudden and extended wholesale price increases could reduce our gross margins and could, if continued over an extended period of time, reduce demand by encouraging our retail customers to conserve or convert to alternative energy sources.

If we fail to design or maintain an effective system of internal controls, including internal controls over financial reporting, we may be unable to report our financial results accurately or prevent fraud, which would likely have a negative impact on the market price of our common units.

          Prior to this offering, we have not been required to file reports with the SEC. Upon the completion of this offering, we will become subject to the public reporting requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act. We prepare our consolidated financial statements in accordance with GAAP, but our internal accounting controls may not currently meet all standards applicable to companies with publicly-traded securities. Effective internal controls are necessary for us to provide reliable financial reports, prevent fraud and to operate successfully as a publicly traded partnership. Our efforts to develop and maintain our internal controls may be unsuccessful, and we may be unable to maintain effective controls over financial reporting, including our disclosure controls, in the future or to comply with our reporting obligations under Section 404 of the Sarbanes-Oxley Act of 2002, or Section 404. For example, Section 404 will require us, among other things, to annually review and report on, and our independent registered public accounting firm to attest to, the effectiveness of our internal controls over financial reporting. We must comply with Section 404 for our fiscal year ending March 31, 2012. We will also be required to perform quarterly evaluations of our disclosure controls beginning the first quarter after we become public and will be required to report the results of each such evaluation in our Form 10-Q each quarter.

          Any failure to develop, implement or maintain effective internal controls over financial reporting and disclosure controls or to improve our internal controls, in particular any identified material weaknesses in such controls, could harm our operating results or cause us to fail to meet our reporting obligations. Given the difficulties inherent in the design and operation of internal controls over financial reporting, we can provide no assurance as to our, or our independent registered public accounting firm's, conclusions about the effectiveness of our internal controls, and we may incur significant costs in our efforts to comply with Section 404. Ineffective internal controls will subject us to regulatory scrutiny and a loss of confidence in our reported financial information, which could have an adverse effect on our business and would likely have a negative effect on the trading price of our common units.

Natural disasters, such as hurricanes, could have an adverse effect on our business, financial condition and results of operations.

          Hurricanes and other natural disasters could cause serious damage or destruction to homes, business structures and the operations of our retail and wholesale customers. For example, any such disaster that occurred in the Gulf Coast region could seriously disrupt the supply of propane and cause serious shortages in various areas, including the areas in which we operate. Such disruptions could potentially have a material adverse impact on our business, financial condition, results of operations and cash flows, which could impair our ability to make distributions to our unitholders.

23

Table of Contents

An impairment of goodwill and intangible assets could reduce our earnings.

          On a combined pro forma basis, as of September 30, 2010, we had reported goodwill and intangible assets of approximately $19.4 million. Such assets are subject to impairment reviews on an annual basis or earlier if information indicates that such asset values have been impaired. Any impairment we would be required to record under GAAP would result in a charge to our income, which would reduce our earnings.

The highly competitive nature of the retail propane business could cause us to lose customers, affect our ability to acquire new customers in our existing locations, thereby reducing our revenues or impairing our ability to expand our operations.

          We encounter competition with other retail propane companies who are larger and have substantially greater financial resources than we do, which may provide them with certain advantages. Also, because of relatively low barriers to entry into the retail propane business, numerous small retail propane distributors, as well as companies not engaged in retail propane distribution, may enter our markets and compete with our retail business. Some rural electric cooperatives and fuel oil distributors have expanded their businesses to include propane distribution. As a result, we are subject to the risk of additional competition in the future. The principal factors influencing competition with other retail propane businesses are:

•

price;



•

reliability and quality of service;



•

responsiveness to customer needs;



•

safety standards and compliance with such standards;



•

long-standing customer relationships;



•

the inconvenience of switching tanks and suppliers; and



•

the lack of growth in the industry.

          We can make no assurances that we will be able to compete successfully on the basis of these factors. If a competitor attempts to increase market share by reducing prices, we may lose customers, which would reduce our revenues.

If we are unable to purchase propane from our principal suppliers, our results of operations would be adversely affected.

          During the fiscal year ended March 31, 2010, three of our suppliers accounted for approximately 51% of our volume of propane purchases on a combined pro forma basis. If we are unable to purchase propane from significant suppliers, our failure to obtain alternate sources of supply at competitive prices and on a timely basis would adversely affect our ability to satisfy customer demand, reduce our revenues and adversely affect our results of operations.

Our business requires extensive credit risk management that may not be adequate to protect against customer nonpayment.

          The risk of nonpayment by customers is a concern in all of our operating segments, and our procedures may not fully eliminate this risk. We manage our credit risk exposure through credit analysis, credit approvals, establishing credit limits, requiring prepayments (partially or wholly), requiring propane deliveries over defined time periods and credit monitoring. While we believe our procedures are effective, we can provide no assurance that bad debt write-offs in the future may not be significant and any such non-payment problems could impact our results of operations and potentially limit our ability to make distributions to our unitholders.

24

Table of Contents

Our business would be adversely affected if service at our principal storage facilities or on the common carrier pipelines we use is interrupted.

          Historically, a substantial portion of our propane supply has originated from storage facilities at Borger, Texas; Conway and Bushton Kansas; Mt. Belvieu, Texas; and Sarnia, Ontario Canada and has been shipped to us or by us to our service areas through seven common carrier pipelines. Any significant interruption in the service at these storage facilities or on the common carrier pipelines we use would adversely affect our ability to obtain propane.

We could be required to provide linefill on certain of the pipelines on which we ship product. This could require the use of our working capital, which could potentially impact our ability to borrow additional amounts under our working capital credit facility to conduct our operations or to make distributions to our unitholders.

          While we have not historically been required to provide the linefill for certain pipelines on which we transport propane and other natural gas liquids, if we were required to provide any portion of the linefill, we would have to purchase propane that would have to remain in the pipeline for an extended period of time. Such a requirement would expose us to inventory and price risk and could negatively impact our working capital position, our liquidity, our availability under our working capital credit facility and our ability to make distributions to our unitholders.

Our propane terminaling operations depend on neighboring pipelines to transport propane.

          We own propane terminals in Jefferson City, Missouri; East St. Louis, Illinois; and St. Catharines, Ontario. These facilities depend on pipeline and storage systems that are owned and operated by third parties. Any interruption of service on the pipeline or lateral connections or adverse change in the terms and conditions of service could have a material adverse effect on our ability, and the ability of our customers, to transport propane to and from our facilities and have a corresponding material adverse effect on our terminaling revenues. In addition, the rates charged by the interconnected pipelines for transportation to and from our facilities affect the utilization and value of our terminaling services. We have historically been able to pass through the costs of pipeline transportation to our customers. However, if competing pipelines do not have similar annual tariff increases or service fee adjustments, such increases could affect our ability to compete, thereby adversely affecting our terminaling revenues.

Our financial results are seasonal and generally lower in the first and second quarters of our fiscal year, which may require us to borrow money to make distributions to our unitholders during these quarters.

          The inventory we have pre-sold to customers is highest during summer months, and our cash receipts are lowest during summer months. As a result, our cash available for distribution for the summer is much lower than for the winter. With lower cash flow during the first and second fiscal quarters, we may be required to borrow money to pay distributions to our unitholders during these quarters. Any restrictions on our ability to borrow money could restrict our ability to pay the minimum quarterly distributions to our unitholders.

We are subject to operating and litigation risks that could adversely affect our operating results to the extent not covered by insurance.

          Our operations are subject to all operating hazards and risks incident to handling, storing, transporting and providing customers with combustible liquids such as propane. As a result, we may be a defendant in various legal proceedings and litigation arising in the ordinary course of business. We are self-insured for non catastrophic occurrences, but not for all risks inherent in our business. We may be unable to maintain or obtain insurance of the type and amount we desire at reasonable rates in the future. As a result of market conditions, premiums and deductibles for certain of our insurance policies

25

Table of Contents

may substantially increase. In some instances, certain insurance could become unavailable or available only for reduced amounts of coverage. We carry limited environmental insurance, thus, losses could occur for uninsurable or uninsured risks or in amounts in excess of existing insurance coverage. The occurrence of an event that is not covered in full or in part by insurance could have a material adverse impact on our business activities, financial condition and results of operations.

Our results of operations and financial condition may be adversely affected by governmental regulation and associated environmental, health, and safety costs.

          The propane business is subject to a wide range of federal, state and local laws and regulations related to environmental, health, and safety matters. These laws and regulations may impose numerous obligations that are applicable to our operations, including obtaining, maintaining and complying with permits to conduct regulated activities, incurring capital or operating expenditures to limit or prevent releases of materials from our facilities, and imposing substantial liabilities and remedial obligations relating to, among other things, emissions into the air and water, habitat and endangered species degradation and the release and disposal of hazardous substances, that may result from our operations. Numerous governmental authorities, such as the U.S. Environmental Protection Agency, or the EPA, and analogous state agencies, have the power to enforce compliance with these laws and regulations and the permits issued under them, oftentimes requiring difficult and costly actions. Failure to comply with these laws, regulations and permits may result in the assessment of administrative, civil and criminal penalties, the imposition of remedial obligations, the suspension or revocation of necessary permits, licenses and authorizations, the requirement that additional pollution controls be installed and the issuance of injunctions limiting or preventing some or all of our operations. In addition, we may experience a delay in obtaining or be unable to obtain required permits, which may cause us to lose potential and current customers, interrupt our operations and limit our growth and revenues.

          Under certain environmental laws that impose strict, joint and several liability, we may be required to remediate our contaminated properties regardless of whether such contamination resulted from the conduct of others or from consequences of our own actions that were in compliance with all applicable laws at the time those actions were taken. In addition, claims for damages to persons, property or natural resources may result from environmental and other impacts of our operations. Moreover, new or modified environmental, health or safety laws, regulations or enforcement policies could be more stringent and impose unforeseen liabilities or significantly increase compliance costs. Therefore, the costs to comply with environmental, health, or safety laws or regulations or the liabilities incurred in connection with them could significantly and adversely affect our business, financial condition or results of operations.

          The United States continues to move towards regulation of "greenhouse gases," including methane, a primary component of natural gas, and carbon dioxide, a byproduct of burning natural gas and oil, and over one-third of the states have already adopted some legal measures to reduce emissions of greenhouse gases, primarily through the planned development of greenhouse gas emission inventories and/or regional greenhouse gas cap-and-trade programs. There were bills pending before the 111th Congress proposing various forms of greenhouse gas regulation, including the American Clean Energy Security, or ACES, Act that, among other things, would have established a cap-and-trade system to regulate greenhouse gas emissions and would have required an 80% reduction in "greenhouse gas" emissions from sources within the United States between 2012 and 2050. Although the ACES Act did not pass the Senate and was not enacted by the 111th Congress, the United States Congress is likely to again consider a climate change bill in the future.

          In December 2009, the EPA issued an "endangerment finding" under the federal Clean Air Act, which allowed the agency to adopt and implement greenhouse gas regulations. In 2010, the EPA adopted and proposed regulations requiring certain mandatory reporting of greenhouse gas emissions, including from upstream oil and gas facilities and large stationary sources of air emissions. Broader regulation is in early stages of development in the United States, and, thus, we are currently unable to

26

Table of Contents

determine the impact of potential greenhouse gas emission control requirements. Mandatory greenhouse gas emissions reductions may impose increased costs on our business and could adversely impact some of our operations. It is possible that broader national or regional greenhouse gas reduction requirements, including on our suppliers, may have direct or indirect adverse impacts on the propane industry. Please read "Business — Government Regulation."

Competition from alternative energy sources may cause us to lose customers, thereby negatively impacting our financial condition and results of operations.

          Propane competes with other sources of energy, some of which are less costly for equivalent energy value. We compete for customers against suppliers of electricity, natural gas and fuel oil. Competition from alternative energy sources, including electricity and natural gas, has increased as a result of reduced regulation of many utilities, including electricity and natural gas. Electricity is a major competitor of propane, but propane has historically enjoyed a competitive price advantage over electricity. Except for some industrial and commercial applications, propane is generally not competitive with natural gas in areas where natural gas pipelines already exist because such pipelines generally make it possible for the delivered cost of natural gas to be less expensive than the bulk delivery of propane. The expansion of natural gas into traditional propane markets has historically been inhibited by the capital cost required to expand distribution and pipeline systems; however, the gradual expansion of the nation's natural gas distribution systems has resulted in natural gas being available in areas that previously depended on propane, which could cause us to lose customers, thereby reducing our revenues. Although propane is similar to fuel oil in some applications and market demand, propane and fuel oil compete to a lesser extent primarily because of the cost of converting from one to the other and due to the fact that both fuel oil and propane have generally developed their own distinct geographic markets. We cannot predict the effect that development of alternative energy sources may have on our operations.

Energy efficiency and new technology may reduce the demand for propane and adversely affect our operating results.

          The national trend toward increased conservation and technological advances, such as installation of improved insulation and the development of more efficient furnaces and other heating devices, has adversely affected the demand for propane by retail customers. Future conservation measures or technological advances in heating, conservation, energy generation or other devices may reduce demand for propane. In addition, if the price of propane increases, some of our customers may increase their conservation efforts and thereby decrease their consumption of propane.

A significant increase in motor fuel prices may adversely affect our profits.

          Motor fuel is a significant operating expense for us in connection with the delivery of propane to our customers. A significant increase in motor fuel prices will result in increased transportation costs to us. The price and supply of motor fuel is unpredictable and fluctuates based on events we cannot control, such as geopolitical developments, supply and demand for oil and gas, actions by oil and gas producers, war and unrest in oil producing countries and regions, regional production patterns and weather concerns. As a result, any increases in these prices may adversely affect our profitability and competitiveness.

The risk of terrorism and political unrest in various energy producing regions may adversely affect the economy and the supply of crude oil and the price and availability of propane, fuel oil and other refined fuels and natural gas.

          An act of terror in any of the major energy producing regions of the world could potentially result in disruptions in the supply of crude oil and natural gas, the major sources of propane, which could have a material impact on the availability and price of propane. Terrorist attacks in the areas of our

27

Table of Contents

operations could negatively impact our ability to transport propane to our locations. These risks could potentially negatively impact our results of operations.

The recent adoption of derivatives legislation by the U.S. Congress could have an adverse effect on our ability to hedge risks associated with our business.

          On July 21, 2010, the Dodd-Frank Wall Street Reform and Consumer Protection Act, or the Dodd-Frank Act, was signed into law. The Dodd-Frank Act regulates derivative transactions, which include certain instruments used in our risk management activities. The Dodd-Frank Act contemplates that most swaps will be required to be cleared through a registered clearing facility and traded on a designated exchange or swap execution facility. There are some exceptions to these requirements for entities that use swaps to hedge or mitigate commercial risk. While we may ultimately be eligible for such exceptions, the scope of these exceptions is currently uncertain at this time, pending further definition through rulemaking proceedings. Among the other provisions of the Dodd-Frank Act that may affect derivative transactions are those relating to establishment of capital and margin requirements for certain derivative participants; establishment of business conduct standards, recordkeeping and reporting requirements; and imposition of position limits. Although the Dodd-Frank Act includes significant new provisions regarding the regulation of derivatives, the impact of those requirements will not be known definitely until regulations have been adopted by the SEC and the Commodities Futures Trading Commission. The new legislation and any new regulations could increase the operational and transactional cost of derivatives contracts and affect the number and/or creditworthiness of available counterparties to us.

We depend on the leadership and involvement of key personnel for the success of our businesses.

          We have certain key individuals in our senior management who we believe are critical to the success of our business. The loss of leadership and involvement of those key management personnel could potentially have a material adverse impact on our business and possibly on the market value of our units.

Risks Inherent in an Investment in Us

Our partnership agreement limits the fiduciary duties of our general partner to our unitholders and restricts the remedies available to our unitholders for actions taken by our general partner that might otherwise be breaches of fiduciary duty.

          Fiduciary duties owed to our unitholders by our general partner are prescribed by law and our partnership agreement. The Delaware Revised Uniform Limited Partnership Act, or the Delaware LP Act, provides that Delaware limited partnerships may, in their partnership agreements, restrict the fiduciary duties owed by the general partner to limited partners and the partnership. Our partnership agreement contains provisions that reduce the standards to which our general partner would otherwise be held by state fiduciary duty law. For example, our partnership agreement:

•

limits the liability and reduces the fiduciary duties of our general partner, while also restricting the remedies available to our unitholders for actions that, without these limitations, might constitute breaches of fiduciary duty. As a result of purchasing common units, our unitholders consent to some actions and conflicts of interest that might otherwise constitute a breach of fiduciary or other duties under applicable state law;



•

permits our general partner to make a number of decisions in its individual capacity, as opposed to in its capacity as our general partner. This entitles our general partner to consider only the interests and factors that it desires, and it has no duty or obligation to give any consideration to any interest of, or factors affecting, us, our affiliates or any limited partner. Examples include the exercise of its limited call right, its voting rights with respect to the units it owns and its determination whether or not to consent to any merger or consolidation of the partnership;

28

Table of Contents

•

provides that our general partner shall not have any liability to us or our unitholders for decisions made in its capacity as general partner so long as it acted in good faith, meaning our general partner subjectively believed that the decision was in, or not opposed to, the best interests of the partnership;



•

generally provides that affiliated transactions and resolutions of conflicts of interest not approved by the Conflicts Committee and not involving a vote of our unitholders must be on terms no less favorable to us than those generally being provided to or available from unrelated third parties or be "fair and reasonable" to us and that, in determining whether a transaction or resolution is "fair and reasonable," our general partner may consider the totality of the relationships between the parties involved, including other transactions that may be particularly favorable or advantageous to us; and



•

provides that our general partner and its officers and directors will not be liable for monetary damages to us or our limited partners for any acts or omissions unless there has been a final and non-appealable judgment entered by a court of competent jurisdiction determining that our general partner or those other persons acted in bad faith or engaged in fraud or willful misconduct.

          By purchasing a common unit, a common unitholder will become bound by the provisions of our partnership agreement, including the provisions described above. Please read "Description of the Common Units — Transfer of Common Units.

Our general partner and its affiliates have conflicts of interest with us and limited fiduciary duties to our unitholders, and they may favor their own interests to the detriment of us and our unitholders.

          Following completion of the offering, the NGL Energy LP Investor Group will own a         % limited partner interest in us (or a         % limited partner interest in us if the underwriters exercise their option to purchase additional common units from us in full), and the NGL Energy GP Investor Group will own and control our general partner and its 0.1% general partner interest in us. Although our general partner has certain fiduciary duties to manage us in a manner beneficial to us and our unitholders, the executive officers and directors of our general partner have a fiduciary duty to manage our general partner in a manner beneficial to its owners. Furthermore, since certain executive officers and directors of our general partner are executive officers or directors of affiliates of our general partner, conflicts of interest may arise between the NGL Energy GP Investor Group and its affiliates, including our general partner, on the one hand, and us and our unitholders, on the other hand. As a result of these conflicts, our general partner may favor its own interests and the interests of its affiliates over the interests of our unitholders. Please read " — Our partnership agreement limits the fiduciary duties of our general partner to our unitholders and restricts the remedies available to our unitholders for actions taken by our general partner that might otherwise be breaches of fiduciary duty." The risk to our unitholders due to such conflicts may arise because of the following factors, among others:

•

our general partner is allowed to take into account the interests of parties other than us, such as members of the NGL Energy GP Investor Group, in resolving conflicts of interest;



•

neither our partnership agreement nor any other agreement requires owners of our general partner to pursue a business strategy that favors us;



•

except in limited circumstances, our general partner has the power and authority to conduct our business without unitholder approval;



•

our general partner determines the amount and timing of asset purchases and sales, borrowings, issuance of additional partnership securities and the creation, reduction or increase of reserves, each of which can affect the amount of cash that is distributed to our unitholders;

29

Table of Contents

•

our general partner determines the amount and timing of any capital expenditures and whether a capital expenditure is classified as a maintenance capital expenditure, which reduces operating surplus, or an expansion capital expenditure, which does not reduce operating surplus. This determination can affect the amount of cash that is distributed to our unitholders and to our general partner and the ability of the subordinated units to convert to common units;



•

our general partner determines which costs incurred by it are reimbursable by us;



•

our general partner may cause us to borrow funds to permit the payment of cash distributions, even if the purpose or effect of the borrowing is to make a distribution on the subordinated units, to make incentive distributions or to accelerate the expiration of the subordination period;



•

our partnership agreement permits us to classify up to $              million as operating surplus, even if it is generated from asset sales, non-working capital borrowings or other sources that would otherwise constitute capital surplus. This cash may be used to fund distributions on our subordinated units or to our general partner in respect of the general partner interest or the incentive distribution rights;



•

our partnership agreement does not restrict our general partner from causing us to pay it or its affiliates for any services rendered to us or entering into additional contractual arrangements with any of these entities on our behalf;



•

our general partner intends to limit its liability regarding our contractual and other obligations;



•

our general partner may exercise its right to call and purchase all of the common units not owned by it and its affiliates if they own more than 80% of the common units;



•

our general partner controls the enforcement of the obligations that it and its affiliates owe to us;



•

our general partner decides whether to retain separate counsel, accountants or others to perform services for us; and



•

our general partner may elect to cause us to issue common units to it in connection with a resetting of the target distribution levels related to our general partner's incentive distribution rights without the approval of the conflicts committee of the board of directors of our general partner or our unitholders. This election may result in lower distributions to our common unitholders in certain situations.

          In addition, certain members of the NGL Energy GP Investor Group and their affiliates currently hold interests in other companies in the energy and natural resource sectors, including the propane industry. Our partnership agreement provides that our general partner will be restricted from engaging in any business activities other than acting as our general partner and those activities incidental to its ownership interest in us. However, members of the NGL Energy GP Investor Group are not prohibited from engaging in other businesses or activities, including those that might be in direct competition with us. As a result, they could potentially compete with us for acquisition opportunities and for new business or extensions of the existing services provided by us.

          Pursuant to the terms of our partnership agreement, the doctrine of corporate opportunity, or any analogous doctrine, does not apply to our general partner or any of its affiliates, including its executive officers, directors and owners. Any such person or entity that becomes aware of a potential transaction, agreement, arrangement or other matter that may be an opportunity for us will not have any duty to communicate or offer such opportunity to us. Any such person or entity will not be liable to us or to any limited partner for breach of any fiduciary duty or other duty by reason of the fact that such person or entity pursues or acquires such opportunity for itself, directs such opportunity to another person or entity or does not communicate such opportunity or information to us. This may create actual and

30

Table of Contents

potential conflicts of interest between us and affiliates of our general partner and result in less than favorable treatment of us and our unitholders. Please read "Conflicts of Interest and Fiduciary Duties."

Even if our unitholders are dissatisfied, they have limited voting rights and are not entitled to elect our general partner or its directors.

          Unlike the holders of common stock in a corporation, unitholders have only limited voting rights on matters affecting our business and, therefore, limited ability to influence management's decisions regarding our business. Unitholders will have no right on an annual or ongoing basis to elect our general partner or its board of directors. The board of directors of our general partner is chosen entirely by its members and not by our unitholders. Unlike publicly-traded corporations, we will not conduct annual meetings of our unitholders to elect directors or conduct other matters routinely conducted at annual meetings of stockholders of corporations. Furthermore, if the unitholders are dissatisfied with the performance of our general partner, they will have limited ability to remove our general partner. As a result of these limitations, the price at which the common units will trade could be diminished because of the absence or reduction of a takeover premium in the trading price. Our partnership agreement also contains provisions limiting the ability of unitholders to call meetings or to acquire information about our operations, as well as other provisions limiting the unitholders' ability to influence the manner or direction of management.

Our partnership agreement restricts the voting rights of unitholders owning 20% or more of our common units.

          Unitholders' voting rights are further restricted by a provision of our partnership agreement providing that any units held by a person that owns 20% or more of any class of units then outstanding, other than our general partner, its affiliates, their direct transferees and their indirect transferees approved by our general partner (which approval may be granted in its sole discretion) and persons who acquired such units with the prior approval of our general partner, cannot vote on any matter.

Our general partner interest or the control of our general partner may be transferred to a third party without the consent of our unitholders.

          Our general partner may transfer its general partner interest to a third party in a merger or in a sale of all or substantially all of its assets without the consent of the unitholders. Furthermore, our partnership agreement does not restrict the ability of the members of the NGL Energy GP Investor Group to transfer all or a portion of its ownership interest in our general partner to a third party. The new owner of our general partner would then be in a position to replace the board of directors and officers of our general partner with its own designees and thereby exert significant control over the decisions made by the board of directors and officers.

The incentive distribution rights of our general partner may be transferred to a third party without unitholder consent.

          Our general partner may transfer its incentive distribution rights to a third party at any time without the consent of our unitholders. If our general partner transfers its incentive distribution rights to a third party but retains its general partner interest, our general partner may not have the same incentive to grow our partnership and increase quarterly distributions to unitholders over time as it would if it had retained ownership of its incentive distribution rights.

31

Table of Contents

Our general partner has a limited call right that may require our unitholders to sell their common units at an undesirable time or price.

          If at any time our general partner and its affiliates own more than 80% of the common units, our general partner will have the right, which it may assign to any of its affiliates or to us, but not the obligation, to acquire all, but not less than all, of the common units held by unaffiliated persons at a price that is not less than their then-current market price, as calculated pursuant to the terms of our partnership agreement. As a result, our unitholders may be required to sell their common units at an undesirable time or price and may not receive any return or a negative return on their investment. Our unitholders may also incur a tax liability upon a sale of their units.

Cost reimbursements to our general partner may be substantial and could reduce our cash available to make quarterly distributions to our unitholders.

          Prior to making any distribution on the common units, we will reimburse our general partner and its affiliates for all expenses they incur on our behalf, which will be determined by our general partner in its sole discretion in accordance with the terms of our partnership agreement. In determining the costs and expenses allocable to us, our general partner is subject to its fiduciary duty, as modified by our partnership agreement, to the limited partners, which requires it to act in good faith. These expenses will include all costs incurred by our general partner and its affiliates in managing and operating us. We are managed and operated by executive officers and directors of our general partner. Please read "Our Cash Distribution Policy and Restrictions on Distributions," "Certain Relationships and Related Party Transactions" and "Conflicts of Interest and Fiduciary Duties — Conflicts of Interest." The reimbursement of expenses and payment of fees, if any, to our general partner and its affiliates will reduce the amount of cash available for distribution to our unitholders.

Our partnership agreement requires that we distribute all of our available cash, which could limit our ability to grow and make acquisitions.

          We expect that we will distribute all of our available cash to our unitholders and will rely primarily on external financing sources, including commercial bank borrowings and the issuance of debt and equity securities, as well as reserves we have established to fund our acquisitions and expansion capital expenditures. As a result, to the extent we are unable to finance growth externally, our cash distribution policy will significantly impair our ability to grow.

          In addition, because we distribute all of our available cash, our growth may not be as fast as that of businesses that reinvest their available cash to expand ongoing operations. To the extent we issue additional units in connection with any acquisitions or expansion capital expenditures, the payment of distributions on those additional units may increase the risk that we will be unable to maintain or increase our per unit distribution level. There are no limitations in our partnership agreement or our revolving credit facility on our ability to issue additional units, including units ranking senior to the common units. The incurrence of additional commercial borrowings or other debt to finance our growth strategy would result in increased interest expense, which, in turn, may impact the available cash that we have to distribute to our unitholders.

We may issue additional units without the approval of our unitholders, which would dilute the interests of existing unitholders.

          Our partnership agreement does not limit the number of additional limited partner interests that we may issue at any time without the approval of our unitholders. Our issuance of additional common units or other equity securities of equal or senior rank will have the following effects:

•

our existing unitholders' proportionate ownership interest in us will decrease;



•

the amount of available cash for distribution on each unit may decrease;

32

Table of Contents

•

because a lower percentage of total outstanding units will be subordinated units, the risk that a shortfall in the payment of the minimum quarterly distribution borne by our common unitholders will increase;



•

the ratio of taxable income to distributions may increase;



•

the relative voting strength of each previously outstanding unit may be diminished; and



•

the market price of the common units may decline.

Our general partner, without the approval of our unitholders, may elect to cause us to issue common units while also maintaining its general partner interest in connection with a resetting of the target distribution levels related to its incentive distribution rights. This could result in lower distributions to our unitholders.

          Our general partner has the right, at any time when there are no subordinated units outstanding and it has received distributions on its incentive distribution rights at the highest level to which it is entitled (48.1%) for each of the prior four consecutive fiscal quarters, to reset the initial target distribution levels at higher levels based on our distributions at the time of the exercise of the reset election. Following a reset election by our general partner, the minimum quarterly distribution will be adjusted to equal the reset minimum quarterly distribution and the target distribution levels will be reset to correspondingly higher levels based on percentage increases above the reset minimum quarterly distribution.

          If our general partner elects to reset the target distribution levels, it will be entitled to receive a number of common units. The number of common units to be issued to our general partner will be equal to that number of common units that would have entitled their holder to an average aggregate quarterly cash distribution in the prior two quarters equal to the average of the distributions to our general partner on the incentive distribution rights in the prior two quarters. We anticipate that our general partner would exercise this reset right to facilitate acquisitions or internal growth projects that would not be sufficiently accretive to cash distributions per common unit without such conversion. It is possible, however, that our general partner could exercise this reset election at a time when it is experiencing, or expects to experience, declines in the cash distributions it receives related to its incentive distribution rights and may, therefore, desire to be issued common units rather than retain the right to receive distributions on its incentive distribution rights based on the initial target distribution levels. As a result, a reset election may cause our common unitholders to experience a reduction in the amount of cash distributions that our common unitholders would have otherwise received had we not issued new common units and general partner interests to our general partner in connection with resetting the target distribution levels.

You will experience immediate and substantial dilution in pro forma net tangible book value of $              per common unit.

          The estimated initial public offering price of $             per common unit exceeds our pro forma net tangible book value of $             per common unit. Based on the estimated initial public offering price of $             per common unit (the midpoint of the price range set forth on the cover of this prospectus), you will incur immediate and substantial dilution of $             per common unit. This dilution results primarily because some of the assets contributed by our general partner and its affiliates are recorded at their historical cost, in accordance with GAAP, and not their fair value. Please read "Dilution."

There is no existing market for our common units, and a trading market that will provide you with adequate liquidity may not develop. The price of our common units may fluctuate significantly, and our unitholders could lose all or part of their investment.

          Prior to this offering, there has been no public market for our common units. After the completion of this offering, there will be only                          publicly traded common units. The NGL Energy LP

33

Table of Contents

Investor Group will own an aggregate of                          common and                          subordinated units, representing an aggregate         % limited partner interest in us. We do not know the extent to which investor interest will lead to the development of a trading market or how liquid that market might be. Our unitholders may be unable to resell their common units at or above the initial public offering price. Additionally, the lack of liquidity may result in wide bid-ask spreads, contribute to significant fluctuations in the market price of the common units and limit the number of investors who are able to buy the common units.

          The initial public offering price for the common units was determined by negotiations between us and the representatives of the underwriters and may not be indicative of the market price of the common units that will prevail in the trading market. The market price of our common units may decline below the initial public offering price. The market price of our common units may also be influenced by many factors, some of which are beyond our control, including:

•

our quarterly distributions;



•

our quarterly or annual earnings or those of other companies in our industry;



•

announcements by us or our competitors of significant contracts or acquisitions;



•

changes in accounting standards, policies, guidance, interpretations or principles;



•

general economic conditions;



•

fluctuations in interest rates;



•

the failure of securities analysts to cover our common units after this offering or changes in financial estimates by analysts;



•

future sales of our common units; and



•

other factors described in these "Risk Factors."

We will incur increased costs as a result of being a publicly traded partnership.

          We have no history operating as a publicly traded partnership. As a publicly traded partnership, we will incur significant legal, accounting and other expenses. In addition, the Sarbanes-Oxley Act of 2002 and related rules subsequently implemented by the SEC and the NYSE, have required changes in the corporate governance practices of publicly traded companies. We expect these rules and regulations to increase our legal and financial compliance costs and to make activities more time-consuming and costly. For example, as a result of becoming a publicly traded partnership, we are required to have at least three independent directors, create an audit committee and adopt policies regarding internal controls and disclosure controls and procedures, including the preparation of reports on internal controls over financial reporting. In addition, we will incur additional costs associated with our publicly traded partnership reporting requirements. We also expect these new rules and regulations to make it more difficult and more expensive for our general partner to obtain director and officer liability insurance and to possibly result in our general partner having to accept reduced policy limits and coverage. As a result, it may be more difficult for our general partner to attract and retain qualified persons to serve on its board of directors or as executive officers. We have included approximately $1.0 million of estimated incremental annual administrative expenses that we expect to incur as a result of being a publicly traded partnership in our financial forecast included elsewhere in this prospectus. However, it is possible that our actual incremental costs of being a publicly traded partnership will be higher than we currently estimate.

34

Table of Contents

Our unitholders' liability may not be limited if a court finds that unitholder action constitutes control of our business.

          A general partner of a partnership generally has unlimited liability for the obligations of the partnership, except for those contractual obligations of the partnership that are expressly made without recourse to the general partner. Our partnership is organized under Delaware law, and we conduct business in a number of other states. The limitations on the liability of holders of limited partner interests for the obligations of a limited partnership have not been clearly established in some of the other states in which we do business. You could be liable for any and all of our obligations as if you were a general partner if a court or government agency were to determine that:

•

we were conducting business in a state but had not complied with that particular state's partnership statute; or



•

a unitholder's right to act with other unitholders to remove or replace our general partner, to approve some amendments to our partnership agreement or to take other actions under our partnership agreement constitute "control" of our business.

          For a discussion of the implications of the limitations of liability on a unitholder, please read "The Partnership Agreement — Limited Liability."

Our unitholders may have liability to repay distributions that were wrongfully distributed to them.

          Under certain circumstances, unitholders may have to repay amounts wrongfully returned or distributed to them. Under Section 17-607 of the Delaware LP Act, we may not make a distribution to you if the distribution would cause our liabilities to exceed the fair value of our assets. Delaware law provides that for a period of three years from the date of an impermissible distribution, limited partners who received the distribution and who knew at the time of the distribution that it violated Delaware law will be liable to the limited partnership for the distribution amount. Substituted limited partners are liable both for the obligations of the assignor to make contributions to the partnership that were known to the substituted limited partner at the time it became a limited partner and for those obligations that were unknown if the liabilities could have been determined from the partnership agreement. Neither liabilities to partners on account of their partnership interests nor liabilities that are non-recourse to the partnership are counted for purposes of determining whether a distribution is permitted. For the purpose of determining the fair value of the assets of a limited partnership, the Delaware LP Act provides that the fair value of property subject to liability for which recourse of creditors is limited shall be included in the assets of the limited partnership only to the extent that the fair value of that property exceeds the nonrecourse liability.

Tax Risks to Common Unitholders

          In addition to reading the following risk factors, you should read "Material Tax Consequences" for a more complete discussion of the expected material federal income tax consequences of owning and disposing of common units.

Our tax treatment depends on our status as a partnership for federal income tax purposes. If the IRS were to treat us as a corporation for federal income tax purposes, our cash available for distribution to our unitholders would be substantially reduced.

          The anticipated after-tax economic benefit of an investment in our common units depends largely on our being treated as a partnership for federal income tax purposes. We have not requested, and do not plan to request, a ruling from the Internal Revenue Service, or IRS, on this or any other tax matter affecting us.

          Despite the fact that we are a limited partnership under Delaware law, it is possible in certain circumstances for a partnership such as ours to be treated as a corporation for federal income tax

35

Table of Contents

purposes. Although we do not believe based on our current operations that we are or will be so treated, a change in our business (or a change in current law) could cause us to be treated as a corporation for federal income tax purposes or otherwise subject us to taxation as an entity.

          If we were treated as a corporation for federal income tax purposes, we would pay federal income tax on our taxable income at the corporate tax rate, which is currently a maximum of 35%, and would likely pay state income tax at varying rates. Distributions to you would generally be taxed again as corporate dividends (to the extent of our current and accumulated earnings and profits), and no income, gains, losses or deductions would flow through to you. Because a tax would be imposed upon us as a corporation, our cash available for distribution to our unitholders would be substantially reduced. Therefore, treatment of us as a corporation would result in a material reduction in the anticipated cash flow and after-tax return to our unitholders, likely causing a substantial reduction in the value of our common units.

          Our partnership agreement provides that if a law is enacted or existing law is modified or interpreted in a manner that subjects us to taxation as a corporation or otherwise subjects us to entity-level taxation for federal income tax purposes, the minimum quarterly distribution amount and the target distribution amounts may be adjusted to reflect the impact of that law on us.

If we were subjected to a material amount of additional entity-level taxation by individual states, it would reduce our cash available for distribution to our unitholders.

          Changes in current state law may subject us to additional entity-level taxation by individual states. Because of widespread state budget deficits and other reasons, several states are evaluating ways to subject partnerships to entity-level taxation through the imposition of state income, franchise and other forms of taxation. Imposition of any such taxes may substantially reduce the cash available for distribution to our unitholders. Our partnership agreement provides that, if a law is enacted or existing law is modified or interpreted in a manner that subjects us to entity-level taxation, the minimum quarterly distribution amount and the target distribution amounts may be adjusted to reflect the impact of that law on us.

The tax treatment of publicly traded partnerships or an investment in our common units could be subject to potential legislative, judicial or administrative changes and differing interpretations, possibly on a retroactive basis.

          The present federal income tax treatment of publicly traded partnerships, including us, or an investment in our common units may be modified by administrative, legislative or judicial interpretation at any time. Recently, members of Congress have considered substantive changes to the existing federal income tax laws that affect certain publicly traded partnerships. Any modification to the federal income tax laws and interpretations thereof may or may not be applied retroactively. Although we are unable to predict whether any of these changes, or other proposals, will ultimately be enacted, any such changes could negatively impact the value of an investment in our common units.

If the IRS contests the federal income tax positions we take, the market for our common units may be adversely impacted and the cost of any IRS contest will reduce our cash available for distribution to our unitholders.

          We have not requested a ruling from the IRS with respect to our treatment as a partnership for federal income tax purposes or any other matter affecting us. The IRS may adopt positions that differ from the conclusions of our counsel expressed in this prospectus or from the positions we take. It may be necessary to resort to administrative or court proceedings to sustain some or all of our counsel's conclusions or the positions we take and such positions may not ultimately be sustained. A court may not agree with some or all of our counsel's conclusions or positions we take. Any contest with the IRS may materially and adversely impact the market for our common units and the price at which they

36

Table of Contents

trade. In addition, our costs of any contest with the IRS will be borne indirectly by our unitholders and our general partner because the costs will reduce our cash available for distribution.

Our unitholders will be required to pay taxes on their share of our income even if they do not receive any cash distributions from us.

          Because our unitholders will be treated as partners to whom we will allocate taxable income which could be different in amount than the cash we distribute, you will be required to pay any federal income taxes and, in some cases, state and local income taxes on your share of our taxable income even if you receive no cash distributions from us. You may not receive cash distributions from us equal to your share of our taxable income or even equal to the actual tax liability that results from that income.

Tax gain or loss on the disposition of our common units could be more or less than expected.

          If you sell your common units, you will recognize a gain or loss equal to the difference between the amount realized and your tax basis in those common units. Because distributions in excess of your allocable share of our net taxable income decrease your tax basis in your common units, the amount, if any, of such prior excess distributions with respect to the units you sell will, in effect, become taxable income to you if you sell such units at a price greater than your tax basis in those units, even if the price you receive is less than your original cost. Furthermore, a substantial portion of the amount realized on any sale of your common units, whether or not representing gain, may be taxed as ordinary income due to potential recapture items, including depreciation recapture. In addition, because the amount realized includes a unitholder's share of our nonrecourse liabilities, if you sell your units, you may incur a tax liability in excess of the amount of cash you receive from the sale. Please read "Material Tax Consequences — Disposition of Common Units — Recognition of Gain or Loss" for a further discussion of the foregoing.

Tax-exempt entities and non-U.S. persons face unique tax issues from owning our common units that may result in adverse tax consequences to them.

          Investment in common units by tax-exempt entities, such as employee benefit plans and individual retirement accounts (known as IRAs), and non-U.S. persons raises issues unique to them. For example, virtually all of our income allocated to organizations that are exempt from federal income tax, including IRAs and other retirement plans, will be unrelated business taxable income and will be taxable to them. Distributions to non-U.S. persons will be reduced by withholding taxes at the highest applicable effective tax rate, and non-U.S. persons will be required to file U.S. federal income tax returns and pay tax on their share of our taxable income. If you are a tax exempt entity or a non-U.S. person, you should consult your tax advisor before investing in our common units.

We will treat each purchaser of common units as having the same tax benefits without regard to the actual common units purchased. The IRS may challenge this treatment, which could adversely affect the value of the common units.

          Because we cannot match transferors and transferees of common units and because of other reasons, we will adopt depreciation and amortization positions that may not conform to all aspects of existing Treasury Regulations. A successful IRS challenge to those positions could adversely affect the amount of tax benefits available to you. It also could affect the timing of these tax benefits or the amount of gain from your sale of common units and could have a negative impact on the value of our common units or result in audit adjustments to your tax returns. Please read "Material Tax Consequences — Tax Consequences of Unit Ownership — Section 754 Election" for a further discussion of the effect of the depreciation and amortization positions we adopted.

37

Table of Contents

We prorate our items of income, gain, loss and deduction for U.S. federal income tax purposes between transferors and transferees of our units each month based on the ownership of our units on the first day of each month, instead of on the basis of the date a particular unit is transferred. The IRS may challenge this treatment, which could change the allocation of items of income, gain, loss and deduction among our unitholders.

          We will prorate our items of income, gain, loss and deduction between transferors and transferees of our units each month based on the ownership of our units on the first day of each month, instead of on the basis of the date a particular unit is transferred. The use of this proration method may not be permitted under existing Treasury Regulations. Recently, however, the U.S. Treasury Department issued proposed Treasury Regulations that provide a safe harbor pursuant to which publicly traded partnerships may use a similar monthly simplifying convention to allocate tax items among transferor and transferee unitholders. Nonetheless, the proposed regulations do not specifically authorize the use of the proration method we have adopted. If the IRS were to challenge our proration method or new Treasury Regulations were issued, we may be required to change the allocation of items of income, gain, loss and deduction among our unitholders. Akin Gump Strauss Hauer & Feld LLP has not rendered an opinion with respect to whether our monthly convention for allocating taxable income and losses is permitted by existing Treasury Regulations. Please read "Material Tax Consequences — Disposition of Common Units — Allocations Between Transferors and Transferees."

A unitholder whose units are loaned to a "short seller" to effect a short sale of units may be considered as having disposed of those common units. If so, such unitholder would no longer be treated for federal income tax purposes as a partner with respect to those common units during the period of the loan and may recognize gain or loss from the disposition.

          Because a unitholder whose units are loaned to a "short seller" to effect a short sale of units may be considered as having disposed of the loaned units, he may no longer be treated for tax purposes as a partner with respect to those units during the period of the loan to the short seller and the unitholder may recognize gain or loss from such disposition. Moreover, during the period of the loan to the short seller, any of our income, gain, loss or deduction with respect to those units may not be reportable by the unitholder and any cash distributions received by the unitholder as to those units could be fully taxable as ordinary income. Akin Gump Strauss Hauer & Feld LLP has not rendered an opinion regarding the treatment of a unitholder where common units are loaned to a short seller to effect a short sale of common units; therefore, unitholders desiring to assure their status as partners and avoid the risk of gain recognition from a loan to a short seller are urged to consult a tax advisor to discuss whether it is advisable to modify any applicable brokerage account agreements to prohibit their brokers from borrowing their units.

We will adopt certain valuation methodologies and monthly conventions for U.S. federal income tax purposes that may result in a shift of income, gain, loss and deduction between our general partner and our unitholders. The IRS may challenge this treatment, which could adversely affect the value of our common units.

          When we issue additional units or engage in certain other transactions, we will determine the fair market value of our assets and allocate any unrealized gain or loss attributable to our assets to the capital accounts of our unitholders and our general partner. Our methodology may be viewed as understating the value of our assets. In that case, there may be a shift of income, gain, loss and deduction between certain unitholders and the general partner, which may be unfavorable to such unitholders. Moreover, under our current valuation methods, subsequent purchasers of common units may have a greater portion of their Internal Revenue Code Section 743(b) adjustment allocated to our tangible assets and a lesser portion allocated to our intangible assets. The IRS may challenge our valuation methods, or our allocation of the Section 743(b) adjustment attributable to our tangible and intangible

38

Table of Contents

assets, and allocations of taxable income, gain, loss and deduction between the general partner and certain of our unitholders.

          A successful IRS challenge to these methods or allocations could adversely affect the amount of taxable income or loss being allocated to our unitholders. It also could affect the amount of taxable gain from our unitholders' sale of common units and could have a negative impact on the value of the common units or result in audit adjustments to our unitholders' tax returns without the benefit of additional deductions. Akin Gump Strauss Hauer & Feld LLP has not rendered an opinion with respect to whether our method for depreciating Section 743 adjustments is sustainable in certain cases.

The sale or exchange of 50% or more of our capital and profits interests during any twelve-month period will result in the termination of our partnership for federal income tax purposes.

          We will be considered to have technically terminated for federal income tax purposes if there is a sale or exchange of 50% or more of the total interests in our capital and profits within a twelve-month period. For purposes of determining whether the 50% threshold has been met, multiple sales of the same unit will be counted only once. While we would continue our existence as a Delaware limited partnership, our technical termination would, among other things, result in the closing of our taxable year for all unitholders, which would result in us filing two tax returns (and our unitholders could receive two Schedules K-1 if relief was not available, as described below) for one fiscal year and could result in a significant deferral of depreciation deductions allowable in computing our taxable income. In the case of a unitholder reporting on a taxable year other than a fiscal year ending December 31, the closing of our taxable year may also result in more than twelve months of our taxable income or loss being includable in his taxable income for the year of termination. A technical termination would not affect our classification as a partnership for federal income tax purposes, but instead, we would be treated as a new partnership for tax purposes. If treated as a new partnership, we must make new tax elections and could be subject to penalties if we are unable to determine that a technical termination occurred. The IRS has recently announced a relief procedure whereby if a publicly traded partnership that has technically terminated requests and the IRS grants special relief, among other things, the partnership will be required to provide only a single Schedule K-1 to unitholders for the tax years in which the termination occurs. Please read "Material Tax Consequences — Disposition of Common Units — Constructive Termination" for a discussion of the consequences of our termination for federal income tax purposes.

As a result of investing in our common units, you may become subject to state and local taxes and return filing requirements in jurisdictions where we operate or own or acquire properties.

          In addition to federal income taxes, you will likely be subject to other taxes, including foreign, state and local taxes, unincorporated business taxes and estate, inheritance or intangible taxes that are imposed by the various jurisdictions in which we conduct business or own or control property now or in the future, even if you do not live in any of those jurisdictions. You will likely be required to file foreign, state and local income tax returns and pay state and local income taxes in some or all of these various jurisdictions. Further, you may be subject to penalties for failure to comply with those requirements. We will own assets and conduct business in a number of jurisdictions, including Georgia, Illinois, Indiana, Kansas, Mississippi, Missouri, Oklahoma and Texas. Each of these states, other than Texas, currently imposes a personal income tax on individuals. Most of these states also impose an income tax on corporations and other entities. As we make acquisitions or expand our business, we may own or control assets or conduct business in additional states that impose a personal income tax. It is your responsibility to file all U.S. federal, foreign, state and local tax returns. Akin Gump Strauss Hauer & Feld LLP has not rendered an opinion on the state or local tax consequences of an investment in our common units.

39

Table of Contents

USE OF PROCEEDS

          We expect to receive net proceeds from the issuance and sale of                          common units offered by this prospectus of approximately $              million after deducting underwriting discounts and commissions and offering expenses (or approximately $              million if the underwriters exercise their option to purchase additional common units from us in full). We intend to use the net proceeds, including the net proceeds from any exercise of the underwriters' option to purchase additional common units from us, to repay amounts outstanding under our revolving credit facility (approximately $              million) and, to the extent that net proceeds remain after all amounts outstanding under our revolving credit facility are repaid, for working capital and general partnership purposes, which may include the acquisition of propane and midstream related businesses. There are no agreements, understandings or commitments with respect to any such acquisition at this time.

          Our $180.0 million revolving credit facility, which matures on October 10, 2014, consists of a $50.0 million working capital facility and a $130.0 million acquisition facility. As of January 31, 2011, we had $74.5 million outstanding under our revolving credit facility, with $6.5 million outstanding under our working capital facility and $68.0 million outstanding under our acquisition facility. Substantially all of the amounts outstanding under our revolving credit facility, which have a weighted average interest rate of 5.75% as of January 31, 2011, were borrowed at the closing of our formation transactions to (i) make cash distributions to NGL Supply and Hicks LLC, (ii) repay assumed indebtedness of NGL Supply and Hicks LLC, (iii) pay the purchase price for Gifford and (iv) pay related transactions costs.

          Our estimates assume an initial public offering price of $             per common unit (the midpoint of the price range set forth on the cover of this prospectus). An increase or decrease in the initial public offering price of $1.00 per common unit would cause the net proceeds from the offering, after deducting underwriting discounts and commissions and offering expenses, to increase or decrease by $              million. If the net proceeds increase due to a higher initial public offering price, we will use the additional proceeds to repay any remaining amounts outstanding under our revolving credit facility and, to the extent that net proceeds remain after all amounts outstanding under our revolving credit facility are repaid, for working capital and general partnership purposes. If the net proceeds decrease due to a lower initial public offering price, we will decrease our repayment of amounts outstanding under our revolving credit facility, or if we are still able to repay all amounts outstanding under our revolving credit facility, we will have less funds available for working capital or general partnership purposes.

          The underwriters may, from time to time, engage in transactions with and perform services for us and our affiliates in the ordinary course of business. Affiliates of                          and                           are lenders under our revolving credit facility and will receive their proportionate share of the repayment of amounts outstanding under our revolving credit facility by us in connection with this offering. Please read "Underwriting."

40

Table of Contents

CAPITALIZATION

          The following table shows:

•

the historical cash and cash equivalents and capitalization of NGL Supply, our predecessor for accounting purposes, as of September 30, 2010;



•

our cash and cash equivalents and capitalization as of September 30, 2010 adjusted to reflect the formation transactions;



•

our pro forma cash and cash equivalents and capitalization as of September 30, 2010, adjusted to give effect to (i) the issuance and sale of                          common units offered by this prospectus at an assumed initial public offering price of $             per common unit (the midpoint of the price range set forth on the cover of this prospectus), (ii) the split of each common unit held by the members of the NGL Energy LP Investor Group into                          common units, (iii) the conversion of                          common units held by the NGL Energy LP Investor Group into                          subordinated units and (iv) the application of the net proceeds from this offering as described in "Use of Proceeds."

          We derived this table from, and it should be read in conjunction with and is qualified in its entirety by reference to, the historical and pro forma financial statements and the related notes included elsewhere in this prospectus. You should also read this table in conjunction with "Management's Discussion and Analysis of Financial Condition and Results of Operations."