EL Paso Pipeline Partners 424B5 Prospectus supplement for primary offering

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Filed Pursuant to Rule 424(b)(5)
Registration No. 333-186887

PROSPECTUS SUPPLEMENT
(To Prospectus dated March 5, 2013)

Common Units Representing Limited Partner Interests having an aggregate offering price of up to $500,000,000

This prospectus supplement and the accompanying prospectus relate to the issuance and sale from time to time of common units representing limited partner interests in El Paso Pipeline Partners, L.P. having an aggregate offering price of up to $500,000,000 through Citigroup Global Markets Inc., as our sales agent. These sales, if any, will be made pursuant to the terms of an equity distribution agreement between us and the sales agent.

Under the terms of the equity distribution agreement, we also may sell common units to Citigroup Global Markets Inc. as principal for its own account at a price agreed upon at the time of the sale. If we sell common units to Citigroup Global Markets Inc. as principal, we will enter into a separate terms agreement with Citigroup Global Markets Inc., and we will describe that agreement in a separate prospectus supplement or pricing supplement.

Our common units trade on the New York Stock Exchange, or NYSE, under the symbol "EPB." On March 6, 2013, the last sale price of our common units as reported on the New York Stock Exchange was $41.56 per common unit. Sales of common units under this prospectus supplement, if any, will be made by means of ordinary brokers' transactions through the facilities of the NYSE at market prices, in block transactions, or as otherwise agreed between us and the sales agent.

The compensation of the sales agent for sales of common units shall be at a fixed commission rate of up to 2% of the gross sales price per common unit. The net proceeds from any sales under this prospectus supplement will be used as described under "Use of Proceeds" in the accompanying prospectus.

As a result of certain Federal Energy Regulatory Commission rate-making policies, we require an owner of our common units to be an Eligible Holder. Eligible Holders are individuals or entities subject to United States federal income taxation on our income or entities not subject to such taxation as long as all of the entity's owners are subject to such taxation.

Investing in our common units involves risks. Please read "Risk Factors" beginning on page S-4 of this prospectus supplement and beginning on page 4 of the accompanying prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement and the accompanying prospectus are truthful or complete. Any representation to the contrary is a criminal offense.

Citigroup

March 7, 2013

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Prospectus Supplement
About this Prospectus Supplement		S-ii
Prospectus Supplement Summary		S-1
Risk Factors		S-4
Use of Proceeds		S-5
Plan of Distribution		S-6
Legal Matters		S-8
Experts		S-8
Incorporation by Reference		S-8
Prospectus
About This Prospectus		1
Where You Can Find More Information		2
About El Paso Pipeline Partners, L.P.		3
Risk Factors		4
Use of Proceeds		5
Description of the Common Units		6
Material Provisions of Our Partnership Agreement		20
Modification of Fiduciary Duties Owed to the Limited Partners		34
Material Tax Consequences		37
Plan of Distribution		53
Legal Matters		54
Experts		54
Cautionary Note Regarding Forward-Looking Statements		55

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering of common units. The second part is the accompanying prospectus, which gives more general information, some of which may not apply to this offering of common units. Generally, when we refer only to the "prospectus," we are referring to both parts combined. If the information about the common unit offering varies between this prospectus supplement and the accompanying prospectus, you should rely on the information in this prospectus supplement.

You should rely only on the information contained or incorporated by reference in this prospectus supplement or the accompanying prospectus or any other information to which we have referred you. We have not authorized anyone to provide you with different information. This prospectus supplement and the accompanying prospectus may only be used where it is legal to sell the offered common units. You should not assume that the information in this prospectus supplement and accompanying prospectus is accurate as of any date other than the respective date on the front cover of those documents. You should not assume that the information incorporated by reference in this prospectus supplement and the accompanying prospectus is accurate as of any date other than the date the respective information was filed with the Securities and Exchange Commission ("SEC"). Our business, financial condition, results of operations and prospects may have changed since those dates.

None of El Paso Pipeline Partners, L.P., the sales agent or any of their respective representatives is making any representation to you regarding the legality of an investment in our common units by you under applicable laws. You should consult with your own advisors as to legal, tax, business, financial and related aspects of an investment in the common units.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights information included or incorporated by reference in this prospectus supplement and the accompanying prospectus. It does not contain all of the information that you should consider before making an investment decision. We urge you to read the entire prospectus supplement, the accompanying prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying prospectus carefully, including the historical financial statements and notes to those financial statements incorporated by reference in this prospectus supplement and the accompanying prospectus. Please read "Risk Factors" and "Information Regarding Forward-Looking Statements" in our Annual Report on Form 10-K for the year ended December 31, 2012 for more information about important risks that you should consider before investing in the common units.

As used in this prospectus supplement, unless the context otherwise indicates, the terms "we," "our," "us," the "partnership," "EPB" or similar terms refer to El Paso Pipeline Partners, L.P. in its individual capacity or to El Paso Pipeline Partners, L.P. and its operating subsidiaries, collectively, as the context requires. References to our "general partner" refer to El Paso Pipeline GP Company, L.L.C. References to "EPB Operating" refer to El Paso Pipeline Partners Operating Company, L.L.C. References in this prospectus to "El Paso" constitute references to El Paso LLC (formerly El Paso Corporation). References to "KMI" refer to Kinder Morgan, Inc. and its controlled affiliates (other than us and our general partner).

El Paso Pipeline Partners, L.P.

We are a Delaware master limited partnership formed in 2007 by El Paso to own and operate interstate natural gas transportation and terminaling facilities. We conduct our operations through EPB Operating, our wholly owned subsidiary. We conduct our business activities through various natural gas pipeline systems and terminaling facilities, including Wyoming Interstate Company, L.L.C., Southern LNG Company, L.L.C., Elba Express Company, L.L.C., Southern Natural Gas Company, L.L.C., Colorado Interstate Gas Company, L.L.C., and Cheyenne Plains Investment Company, L.L.C., which owns Cheyenne Plains Gas Pipeline Company, L.L.C.

Our systems provide a significant portion of our transportation, storage and terminaling services through firm contracts that obligate our customers to pay a fixed monthly reservation or demand charge. When a customer uses the reserved capacity, our systems also collect usage charges based on the volume of natural gas actually transported or stored, which enables us to recover the system's variable costs. Any portion of physical capacity under firm contracts that is not utilized may be used for interruptible service. We believe that the high percentage of earnings derived from capacity reservation charges mitigates the risk of earnings fluctuations caused by changing supply and demand conditions.

Approximately 93% of our 2012 revenues were collected in the form of demand or reservation charges. As of December 31, 2012, the remaining weighted average contract life of our natural gas transportation and LNG contracts was approximately 8 years and 20 years, respectively.

Our Relationship with El Paso and Kinder Morgan, Inc.

El Paso is a wholly owned subsidiary of KMI. KMI and its affiliates own our 2% general partner interest, all of our incentive distribution rights and an approximate 41% limited partner interest in us.

KMI owns an interest in or operates approximately 75,000 miles of pipelines and 180 terminals. KMI's pipelines transport natural gas, gasoline, crude oil, carbon dioxide (CO₂) and other products, and its terminals store petroleum products and chemicals and handle such products as ethanol, coal, petroleum coke and steel. KMI also owns the general partner and approximately 11% of the limited partner interests of Kinder Morgan Energy Partners, L.P., a publicly-traded master limited partnership in North America.

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Business Strategies

Our business strategy is to:

•: Focus on stable, fee-based energy transportation and storage assets that are central to the energy infrastructure of growing markets within North America;
•: Increase utilization of our existing assets while controlling costs, operating safely and employing environmentally sound operating practices;
•: Leverage economies of scale from incremental acquisitions and expansions of assets that fit within our strategy and are accretive to cash flow; and
•: Maximize the benefits of our financial structure to create and return value to our unitholders.

It is our intention to carry out the above business strategy, modified as necessary to reflect changing economic conditions and other circumstances. However, as discussed under "Risk Factors," there are factors that could affect our ability to carry out our strategy or affect its level of success even if carried out.

We regularly consider and enter into discussions regarding potential acquisitions, including those from KMI or its affiliates, and are currently contemplating potential acquisitions. Any such transaction would be subject to negotiation of mutually agreeable terms and conditions, receipt of fairness opinions and approval of the parties' respective boards of directors. While there are currently no unannounced purchase agreements for the acquisition of any material business or assets, such transactions can be effected quickly, may occur at any time and may be significant in size relative to our existing assets or operations.

Our Executive Offices

Our principal executive offices are located at the 1001 Louisiana Street, Suite 1000, Houston, Texas 77002, and our telephone number is (713) 369-9000.

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THE OFFERING


Common Units Offered by Us		Common units having an aggregate offering price of up to $500,000,000.
New York Stock Exchange Symbol		EPB
Use of Proceeds		We will use the net proceeds of this offering, after deducting the sales agent's commission and our offering expenses, for general partnership purposes.
Risk Factors		An investment in our common units involves risk. Please read "Risk Factors" and other information included, or incorporated by reference, in this prospectus supplement and the accompanying prospectus for a discussion of factors you should carefully consider before deciding to invest in our common units.
Eligible Holders and Redemption		Only Eligible Holders will be entitled to receive distributions or be allocated income or loss from us. Eligible Holders are:
		• individuals or entities subject to United States federal income taxation on the income generated by us; or
		• entities that, while not subject to United States federal taxation on the income generated by us, have owners that are all subject to such taxation.
		We have the right, which we may assign to any of our affiliates, but not the obligation, to redeem all of the units of any holder that is not an Eligible Holder or that has failed to certify or has falsely certified that such holder is an Eligible Holder. The purchase price for such redemption would be equal to the lower of the holder's purchase price and the then-current market price of the units. The redemption price will be paid in cash or by delivery of a promissory note, as determined by our general partner.
		Please read "Description of the Common Units—Transfer of Common Units" and "Material Provisions of Our Partnership Agreement—Non-Taxpaying Assignees; Redemption" in the accompanying prospectus.

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RISK FACTORS

An investment in our common units involves risk. You should carefully read the risk factors set forth in our annual and quarterly reports filed with the SEC, together with all of the other information included in, or incorporated by reference into, this prospectus supplement and the accompanying prospectus, when evaluating an investment in our common units.

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USE OF PROCEEDS

We will use the net proceeds of this offering, after deducting the sales agent's commission and our offering expenses, for general partnership purposes as described in the accompanying prospectus. An affiliate of the sales agent is a lender under our revolving credit facility which matures on May 27, 2016. If we use any net proceeds of this offering to repay borrowings under the revolving credit facility, then the sales agent and its affiliated and associated persons may receive proceeds from this offering.

As of December 31, 2012, we had no outstanding balance under our revolving credit facility and $8 million outstanding in letters of credit. We use our revolving credit facility to fund capital expenditures and working capital requirements and for general partnership purposes.

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PLAN OF DISTRIBUTION

We have entered into an equity distribution agreement with Citigroup Global Markets Inc. under which we may offer and sell common units having an aggregate offering price of up to $500 million from time to time through Citigroup Global Markets Inc., as our sales agent. Sales of the common units, if any, will be made by means of ordinary brokers' transactions on the NYSE at market prices, block transactions and such other transactions as agreed upon by us and the sales agent. As agent, Citigroup Global Markets Inc. will not engage in any transactions that stabilize the price of our common units.

Citigroup Global Markets Inc. will use its reasonable efforts, as our sales agent, to sell the common units offered pursuant to this prospectus supplement on a daily basis or as otherwise agreed upon by us and the sales agent. We will designate the maximum number of common units to be sold through the sales agent, on a daily basis or otherwise as we and the sales agent agree. Subject to the terms and conditions of the equity distribution agreement, Citigroup Global Markets Inc. will use its reasonable efforts as the sales agent to sell, as our sales agent and on our behalf, all of the designated common units. We may instruct the sales agent not to sell common units if the sales cannot be effected at or above the price designated by us in any such instruction. Either we or the sales agent may suspend the offering of common units pursuant to the equity distribution agreement by notifying the other party.

The commission to be paid to the sales agent for units sold through it pursuant to the equity distribution agreement shall be at a fixed rate of up to 2% of the gross sales price per unit. The remaining sales proceeds, after deducting the applicable commission and any expenses payable by us and any transaction fees imposed by any governmental or self-regulatory organization in connection with the sales, will equal our net proceeds from the sale of the common units.

Settlement for sales of common units will occur on the third business day following the date on which any sales were made. There is no arrangement for funds to be received in an escrow, trust or similar arrangement.

In connection with the sale of the common units on our behalf, Citigroup Global Markets Inc. may be deemed to be an "underwriter" within the meaning of the Securities Act of 1933, as amended, and the compensation paid to Citigroup Global Markets Inc. may be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to the sales agent against certain liabilities, including civil liabilities under the Securities Act. We have also agreed to reimburse the sales agent for certain of its expenses.

Citigroup Global Markets Inc. and its related entities have, from time to time, performed, and may in the future perform, various financial advisory and commercial and investment banking services for us and our affiliates, for which they have received and in the future will receive customary compensation and expense reimbursement.

In compliance with the guidelines of the Financial Industry Regulatory Authority, Inc., or FINRA, the maximum discount or commission to be received by any FINRA member or independent broker-dealer may not exceed 8% of the aggregate offering price of the common units offered pursuant to this prospectus supplement. An affiliate of Citigroup Global Markets Inc. is a lender under our revolving bank credit facility. If we use any net proceeds of this offering to repay borrowings under the credit facility, Citigroup Global Markets Inc. and its affiliates and associated persons may receive proceeds

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from this offering. Because FINRA views the common units offered hereby as interests in a direct participation program, this offering is being made in compliance with Rule 2310 of the FINRA Rules.

If we or the sales agent have reason to believe that our common units are no longer an "actively-traded security" as defined under Rule 101(c)(l) of Regulation M under the Securities Exchange Act of 1934, as amended, that party will promptly notify the other and sales of common units pursuant to the equity distribution agreement or any terms agreement will be suspended until in our collective judgment that or other exemptive provisions have been satisfied.

The offering of common units pursuant to the equity distribution agreement will terminate upon the earlier of (1) the sale of all common units subject to the equity distribution agreement or (2) the termination of the equity distribution agreement by us or by the sales agent.

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LEGAL MATTERS

Andrews Kurth LLP, Houston, Texas, will pass upon the validity of the common units offered hereby and various other legal matters in connection with the offering on our behalf. Vinson & Elkins L.L.P., Houston, Texas, will pass upon certain legal matters in connection with the offering on behalf of the sales agent.

EXPERTS

The financial statements as of December 31, 2012 and for the year ended December 31, 2012 and management's assessment of the effectiveness of internal control over financial reporting (which is included in Management's Report on Internal Control over Financial Reporting) as of December 31, 2012 incorporated in this prospectus supplement and accompanying prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2012 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

The consolidated financial statements of El Paso Pipeline Partners, L.P. at December 31, 2011, and for each of the two years in the period ended December 31, 2011 appearing in El Paso Pipeline Partners, L.P.'s Annual Report (Form 10-K) for the year ended December 31, 2012 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

INCORPORATION BY REFERENCE

The SEC allows us to "incorporate by reference" information into this document. This means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus, and information that we file later with the SEC will automatically update and supersede the previously filed information. We incorporate by reference the documents listed below and any future filings made by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, excluding information deemed to be furnished and not filed with the SEC, until all the securities are sold:

•: Annual Report on Form 10-K (File No. 001-33825) for the fiscal year ended December 31, 2012, filed on February 26, 2013;
•: Current Reports on Form 8-K (File No. 001-33825) filed on January 16, 2013 and January 31, 2013; and
•: The description of our common units contained in our registration statement on Form 8-A (File No. 001-33825), filed on November 13, 2007.

Each of these documents is available from the SEC's website and public reference rooms, as described in "Where You Can Find More Information" on page 2 of the accompanying prospectus. Through our website,http://www.kindermorgan.com, you can access electronic copies of documents we file with the SEC, including our annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K and any amendments to those reports. Information on our website is not incorporated by reference in this prospectus. Access to those electronic filings is available as soon as reasonably practical after filing with the SEC. You may also request a copy of those filings, including any exhibit specifically incorporated by reference to those documents, at no cost by writing or telephoning Investor Relations, El Paso Pipeline Partners, L.P., at our principal executive office, which is: 1001 Louisiana Street, Suite 1000, Houston, Texas 77002; Telephone: (713) 369-9000.

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PROSPECTUS

$500,000,000

EL PASO PIPELINE PARTNERS, L.P.

Common Units Representing Limited Partner Interests

We may offer and sell common units in amounts, at prices and on terms to be determined by market conditions and other factors at the time of our offerings. This prospectus provides you with a general description of the common units we may offer and the manner in which they may be offered. Each time we sell common units we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read this prospectus and the applicable prospectus supplement and the documents incorporated by reference herein and therein carefully before you invest in our common units. This prospectus may not be used to consummate sales of our common units unless accompanied by a prospectus supplement.

El Paso Pipeline Partners, L.P. common units are listed for trading on the New York Stock Exchange under the symbol "EPB."

Investing in our common units involves risk. Limited partnerships are inherently different from corporations. For a discussion of the factors you should consider before deciding to purchase our common units, please see "Risk Factors," beginning on page 4 of this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is March 5, 2013.

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ABOUT THIS PROSPECTUS			1
WHERE YOU CAN FIND MORE INFORMATION			2
ABOUT EL PASO PIPELINE PARTNERS, L.P.			3
RISK FACTORS			4
USE OF PROCEEDS			5
DESCRIPTION OF THE COMMON UNITS			6
MATERIAL PROVISIONS OF OUR PARTNERSHIP AGREEMENT			20
MODIFICATION OF FIDUCIARY DUTIES OWED TO THE LIMITED PARTNERS			34
MATERIAL TAX CONSEQUENCES			37
PLAN OF DISTRIBUTION			53
LEGAL MATTERS			54
EXPERTS			54
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS			55

You should rely only on the information contained or incorporated by reference in this prospectus. We have not authorized anyone to provide you with different information. This prospectus may only be used where it is legal to sell the offered securities. You should not assume that the information in this prospectus or any prospectus supplement is accurate as of any date other than the respective dates on the front covers of those documents. You should not assume that the information incorporated by reference in this prospectus is accurate as of any date other than the date the respective information was filed with the Securities and Exchange Commission. Our business, financial condition, results of operations and prospects may have changed since those dates.

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the "SEC") under the Securities Act of 1933, as amended (the "Securities Act"), using a shelf registration process. Using this shelf registration process, we may offer and sell our common units in one or more offerings up to a dollar amount of proceeds of $500,000,000. This prospectus does not contain all of the information set forth in the registration statement, or the exhibits that are a part of the registration statement, parts of which are omitted as permitted by the rules and regulations of the SEC. For further information about us and about the securities to be sold pursuant to this prospectus, please refer to the information below and to the registration statement and the exhibits that are a part of the registration statement.

Each time we sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering and the securities offered by us in that offering. The prospectus supplement may also add, update or change information in this prospectus.

In this prospectus, references to "EPB" mean El Paso Pipeline Partners, L.P. Unless context requires otherwise, references to "we," "us" and "our" mean El Paso Pipeline Partners, L.P. and its consolidated subsidiaries, including El Paso Pipeline Partners Operating Company, L.L.C. References to "EPB Operating" mean El Paso Pipeline Partners Operating Company, L.L.C.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports and other information with the SEC. The SEC allows us to incorporate by reference into this prospectus the information we file with it, which means that we can disclose important information to you by referring you to those documents. This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by reference to the actual documents. The information incorporated by reference is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information as well as the information included in this prospectus. Some documents or information, such as that called for by Items 2.02 and 7.01 of Form 8-K, or the exhibits related thereto under Item 9.01 of Form 8-K, are deemed furnished and not filed in accordance with SEC rules. None of those documents and none of that information is incorporated by reference into this prospectus. We incorporate by reference the following documents:

•: Annual Report on Form 10-K (File No. 001- 33825) for the year ended December 31, 2012, filed on February 26, 2013;
•: Current Reports on Form 8-K (File No. 001- 33825) filed on January 16, 2013 and January 31, 2013;
•: The description of our common units contained in our registration statement on Form 8-A (File No. 001-33825), filed on November 13, 2007; and
•: All documents filed with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), between the date of this prospectus and the completion of the sale of securities offered hereby.

The SEC maintains an Internet web site that contains reports, proxy and information statements and other material that are filed through the SEC's Electronic Data Gathering, Analysis and Retrieval (EDGAR) System. This system can be accessed athttp://www.sec.gov. You can find information we file with the SEC by reference to our partnership name or to our SEC file number, 001-33825. You also may read and copy any document we file with the SEC at the SEC's public reference room located at:

100 F Street, N.E., Room 1580
Washington, D.C. 20549

Please call the SEC at 1-800-SEC-0330 for further information about the public reference room and its copy charges. Our SEC filings are also available to the public through the New York Stock Exchange, on which our common units are listed, at 20 Broad Street, New York, New York 10005.

We will provide a copy of any document incorporated by reference in this prospectus and any exhibit specifically incorporated by reference in those documents, without charge, by written or oral request directed to us at the following address and telephone number:

El Paso Pipeline Partners, L.P.
Investor Relations Department
1001 Louisiana Street, Suite 1000
Houston, Texas 77002
(713) 369-9000

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ABOUT EL PASO PIPELINE PARTNERS, L.P.

EPB is a Delaware master limited partnership formed in November 2007 by El Paso LLC (formerly El Paso Corporation) ("El Paso") to own and operate interstate natural gas transportation and terminaling facilities. EPB conducts its operations through EPB Operating, its wholly owned subsidiary. We conduct our business activities through various natural gas pipeline systems and terminaling facilities, including Wyoming Interstate Company, L.L.C., Southern LNG Company, L.L.C., Elba Express Company, L.L.C., Southern Natural Gas Company, L.L.C., Colorado Interstate Gas Company, L.L.C., and Cheyenne Plains Investment Company, L.L.C., which owns Cheyenne Plains Gas Pipeline Company, L.L.C.

Our systems transport and store natural gas for natural gas distribution and industrial companies, electric generation companies, natural gas producers, other natural gas pipelines and natural gas marketing and trading companies. Our pipeline systems, storage facilities and liquid natural gas ("LNG") receiving terminal operate under tariffs approved by the Federal Energy Regulatory Commission ("FERC") that establish rates, cost recovery mechanisms and other terms and conditions of services to our customers. The fees or rates established under our tariff are a function of our cost of providing services to our customers, including a reasonable return on our invested capital.

We are controlled by our general partner, El Paso Pipeline GP Company, L.L.C., a wholly owned subsidiary of El Paso. El Paso is a wholly owned subsidiary of Kinder Morgan, Inc. ("KMI").

The address of our principal executive offices is 1001 Louisiana Street, Suite 1000, Houston, Texas 77002, and our telephone number at this address is (713) 369-9000.

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RISK FACTORS

Limited partner interests are inherently different from the 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 a similar business. Before you invest in our common units, you should carefully consider the risk factors included in our most-recent annual report on Form 10-K, our quarterly reports on Form 10-Q and our current reports on Form 8-K that are incorporated herein by reference and those that may be included in the applicable prospectus supplement, together with all of the other information included in this prospectus, any prospectus supplement and the documents we incorporate by reference.

If any of the risks discussed in the foregoing documents were actually to occur, our business, financial condition, results of operations, or cash flow could be materially adversely affected. In that case, our ability to make distributions to our unitholders may be reduced, the trading price of our common units could decline and you could lose all or part of your investment.

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USE OF PROCEEDS

Unless we inform you otherwise in a prospectus supplement, we intend to use the net proceeds from the sale of common units we are offering for general partnership purposes. This may include, among other things, additions to working capital, repayment or refinancing of existing indebtedness or other partnership obligations, financing of capital expenditures and acquisitions, investment in existing and future projects, and repurchases and redemptions of securities. Pending any specific application, we may initially invest funds in short-term marketable securities or apply them to the reduction of other indebtedness.

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DESCRIPTION OF THE COMMON UNITS

Number of Common Units

As of January 31, 2013, we had 215,789,325 common units outstanding, including 90,320,810 common units held by affiliates of our general partner. Our limited partnership agreement does not limit the number of common units we may issue.

Where Common Units Are Traded

Our common units are listed for trading on the New York Stock Exchange under the symbol "EPB."

Quarterly Distributions

Set forth below is a summary of the significant provisions of our partnership agreement that relate to cash distributions.

Distributions of Available Cash

General

Our partnership agreement requires that, within 45 days after the end of each quarter, we distribute all of our available cash to unitholders of record on the applicable record date.

Definition of Available Cash

Available cash, for any quarter, consists of all cash on hand at the end of that quarter:

•

less the amount of cash reserves established by our general partner to:

•: provide for the proper conduct of our business, including necessary maintenance capital expenditures;
•: comply with applicable law, any of our debt instruments or other agreements; or
•: provide funds for distributions to our unitholders and to our general partner for any one or more of the next four quarters;

•

plus, all cash on hand on the date of determination resulting from cash received after the end of that quarter in respect of our ownership interests in any entity that is not wholly owned and attributable to their operations during that quarter; and

•

plus, if our general partner so determines, all or a portion of cash on hand on the date of determination of available cash for the quarter resulting from Working Capital Borrowings made subsequent to the end of such quarter.

Working Capital Borrowings are generally borrowings that are made under a credit facility or another arrangement, are used solely for working capital purposes or to pay distributions to unitholders and are intended to be repaid within 12 months.

Intent to Distribute Minimum Quarterly Distribution

We will distribute to the holders of common units on a quarterly basis at least the minimum quarterly distribution of $0.28750 per unit, or $1.15 per unit per year, to the extent we have sufficient cash from our operations after establishment of cash reserves and payment of fees and expenses, including payments to our general partner. However, there is no guarantee that we will pay the minimum quarterly distribution on the units in any quarter. Even if our cash distribution policy is not

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modified or revoked, the amount of distributions paid under our policy and the decision to make any distribution are determined by our general partner, taking into consideration the terms of our partnership agreement. We are prohibited from making any distributions to unitholders if it would cause an event of default, or an event of default is existing, under our credit agreement.

General Partner Interest and Incentive Distribution Rights

Our general partner is currently entitled to two percent of all quarterly distributions since inception that we make prior to our liquidation. This general partner interest is represented by general partner units. Our general partner has the right, but not the obligation, to contribute a proportionate amount of capital to us to maintain its current general partner interest. The general partner's two percent interest in these distributions will be reduced if we issue additional units in the future and our general partner does not contribute a proportionate amount of capital to us to maintain its two percent general partner interest.

Our general partner also currently holds incentive distribution rights that entitle it to receive increasing percentages, up to a maximum of 50 percent, of the cash we distribute from operating surplus (as defined below) in excess of $0.33063 per unit per quarter. The maximum distribution of 50 percent includes distributions paid to our general partner on its two percent general partner interest and assumes that our general partner maintains its general partner interest at two percent. The maximum distribution of 50 percent does not include any distributions that our general partner or its affiliates may receive on common units that they own. Please read "—General Partner Interest and Incentive Distribution Rights" for additional information.

Operating Surplus and Capital Surplus

General

All cash distributed to unitholders is characterized as either "operating surplus" or "capital surplus." Our partnership agreement requires that we distribute available cash from operating surplus differently than available cash from capital surplus.

Operating Surplus

We define operating surplus in the partnership agreement and for any period it generally means:

•: $50 million (as described below); plus
•: all of our cash receipts after the closing of our initial public offering (other than pursuant to the next bullet), excluding cash from interim capital transactions (as defined below); plus
•: all of our cash receipts after the end of a quarter but before the date of determination resulting from cash distributions paid on our ownership interest in any entity that is not wholly owned (excluding any such amounts constituting the proceeds from interim capital transactions at any entity that is not wholly owned); plus
•: Working Capital Borrowings made after the end of a quarter but before the date of determination of operating surplus for the quarter; plus
•: cash distributions paid on equity issued to finance all or a portion of the construction, acquisition or improvement (such as equipment or facilities) in respect of the period beginning on the date that we enter into a binding obligation to commence the construction, acquisition or improvement of a capital improvement or replacement of a capital asset and ending on the earlier to occur of the date the capital improvement or capital asset commences commercial service or the date that it is abandoned or disposed of; less

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•: our Operating Expenditures (as defined below) after the closing of our initial public offering, including maintenance capital expenditures (including capital contributions to any entity which we are, or will be, an equity owner, to be used by such entity for maintenance capital expenditures); less
•: the amount of cash reserves established by our general partner to provide funds for future Operating Expenditures; less
•: all Working Capital Borrowings not repaid within twelve months after having been incurred.

As described above, operating surplus does not reflect actual cash on hand that is available for distribution to our unitholders. For example, it includes a provision that enables us, if we choose, to distribute as operating surplus up to $50 million of cash we receive in the future from non-operating sources such as asset sales, issuances of securities and long-term borrowings that would otherwise be distributed as capital surplus. In addition, the effect of including, as described above, certain cash distributions on equity securities in operating surplus would be to increase operating surplus by the amount of any such cash distributions. As a result, we may also distribute as operating surplus up to the amount of any such cash distributions we receive from non-operating sources.

If a Working Capital Borrowing, which increases operating surplus, is not repaid during the 12-month period following the borrowing, it will be deemed repaid at the end of such period, thus decreasing operating surplus at such time. When such Working Capital Borrowing is in fact repaid, it will not be treated as a further reduction to operating surplus because operating surplus will have been previously reduced by the deemed repayment.

We define Operating Expenditures in the partnership agreement, and it generally means all of our expenditures, including, but not limited to, taxes, payments to our general partner, reimbursement of expenses incurred by our general partner or its affiliates on our behalf, non-pro rata purchases of units, interest payments, payments made in the ordinary course of business under interest rate swap agreements and commodity hedge contracts, repayments of Working Capital Borrowings and maintenance capital expenditures, provided that Operating Expenditures will not include:

•: repayment of Working Capital Borrowings deducted from operating surplus pursuant to the last bullet point of the definition of operating surplus above when such repayment actually occurs;
•: payments (including prepayments and prepayment penalties) of principal of and premium on indebtedness, other than Working Capital Borrowings;
•: expansion capital expenditures;
•: investment capital expenditures, including additional capital contributions to any entity which we are, or will be, an equity owner, to be used by such entity for investment capital expenditures;
•: payment of transaction expenses relating to interim capital transactions (as defined below);
•: distributions to our partners (including distributions in respect of our Class B units and incentive distribution rights); or
•: non-pro rata purchases of units of any class made with the proceeds of an interim capital transaction.

Maintenance capital expenditures represent capital expenditures made to replace partially or fully depreciated assets, to maintain the existing operating capacity of our assets and to extend their useful lives, or other capital expenditures that are incurred in maintaining existing system volumes or our asset base. Costs for repairs and minor renewals to maintain facilities in operating condition and that do not extend the useful life of existing assets are treated as operations and maintenance expenses as we incur them. Maintenance capital expenditures also include interest (and related fees) on debt incurred and

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distributions on equity issued to finance all or any portion of the construction, improvement or development of a replacement asset that is paid in respect of the period that begins when we enter into a binding commitment or commence constructing or developing a replacement asset and ending on the earlier to occur of the date any such replacement asset commences commercial service or the date it is abandoned or disposed of (which will include any such amounts included in the account known as the allowance for funds used during construction (AFUDC) maintained by our interstate natural gas pipelines, storage operations and liquefied natural gas receiving terminal in accordance with FERC regulations). Maintenance capital expenditures include contributions made by us to any entity which we are, or will be, an equity owner, to be used by such entity for maintenance capital expenditures. Capital expenditures made solely for investment purposes are not considered maintenance capital expenditures.

Expansion capital expenditures are those capital expenditures made to increase the long-term operating capacity of our assets or our asset base whether through construction or acquisition. Examples of expansion capital expenditures include the acquisition of equipment, or the construction, development or acquisition of additional pipeline, compression equipment or storage capacity, to the extent such capital expenditures are expected to expand for the long-term either our operating capacity or asset base. Expansion capital expenditures also include interest (and related fees) on debt incurred and distributions on equity issued to finance all or any portion of the construction of such a capital improvement in respect of the period that commences when we enter into a binding obligation to commence construction of a capital improvement and ending on the date such capital improvement commences commercial service or the date that it is abandoned or disposed of (which includes any such amounts included in the account known as the allowance for funds used during construction (AFUDC) maintained by our interstate natural gas pipelines, storage operations and liquefied natural gas receiving terminal in accordance with FERC regulations). Expansion capital expenditures include contributions made by us to any entity which we are, or will be, an equity owner, to be used by such entity for expansion capital expenditures. Capital expenditures made solely for investment purposes are not considered expansion capital expenditures.

Investment capital expenditures are those capital expenditures that are neither maintenance capital expenditures nor expansion capital expenditures. Investment capital expenditures largely consist of capital expenditures made for investment purposes. Examples of investment capital expenditures include traditional capital expenditures for investment purposes, such as purchases of securities, as well as other capital expenditures that might be made in lieu of such traditional investment capital expenditures, such as the acquisition of a capital asset for investment purposes or development of facilities that are in excess of the maintenance of our existing operating capacity or operating income, but which are not expected to expand for the long-term our operating capacity or asset base. Investment capital expenditures include contributions made by us to any entity which we are, or will be, an equity owner, to be used by such entity for investment capital expenditures.

As described above, none of our investment capital expenditures or expansion capital expenditures are subtracted from operating surplus. Because investment capital expenditures and expansion capital expenditures include interest payments (and related fees) on debt incurred and distributions on equity issued to finance all of the portion of the construction, replacement or improvement of a capital asset (such as additional pipelines, compression equipment or storage capacity) in respect of the period that begins when we enter into a binding obligation to commence construction of a capital improvement and ending on the earlier to occur of the date any such capital asset commences commercial service or the date that it is abandoned or disposed of, such interest payments and equity distributions are also not subtracted from operating surplus.

Pursuant to our partnership agreement, capital expenditures that are made in part for maintenance capital purposes and in part for investment capital or expansion capital purposes are allocated as maintenance capital expenditures, investment capital expenditures or expansion capital expenditure by our general partner, with the concurrence of our conflicts committee.

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Capital Surplus

We also define capital surplus in the partnership agreement and in "—Characterization of Cash Distributions" below, and it will generally be generated only by the following, which we call "interim capital transactions":

•: borrowings other than Working Capital Borrowings;
•: sales of our equity and debt securities;
•: sales or other dispositions of assets for cash, other than inventory, accounts receivable and other current assets sold in the ordinary course of business or as part of normal retirement or replacement of assets;
•: the termination of interest rate swap agreements or commodity hedge contracts prior to the termination date specified therein;
•: capital contributions received by us or, in the case of any partially owned entity, from the unaffiliated partner(s) or other owner(s) of such entity; and
•: corporate reorganizations or restructurings.

Characterization of Cash Distributions

Our partnership agreement requires that we treat all available cash distributed as coming from operating surplus until the sum of all available cash distributed equals the operating surplus as of the most recent date of determination of available cash. Our partnership agreement requires that we treat any amount distributed in excess of operating surplus, regardless of its source, as capital surplus. As reflected above, operating surplus includes $50 million, which does not reflect actual cash on hand that is available for distribution to our unitholders. Rather, it is a provision that enables us, if we choose, to distribute as operating surplus up to this amount of cash we receive in the future from interim capital transactions, that would otherwise be distributed as capital surplus. We have not and we do not anticipate that we will make any distributions from capital surplus. The characterization of cash distributions as operating surplus versus capital surplus does not result in a different impact to unitholders for federal tax purposes. Please read "Material Tax Considerations—Tax Consequences of Unit Ownership—Treatment of Distributions" for a discussion of the tax treatment of cash distributions.

Distributions of Available Cash from Operating Surplus

Our partnership agreement requires that we make distributions of available cash from operating surplus in the following manner:

•: first, 98 percent to all unitholders, pro rata, and two percent to the general partner, until we distribute for each outstanding unit an amount equal to the minimum quarterly distribution for that quarter; and
•: thereafter, in the manner described in "—General Partner Interest and Incentive Distribution Rights" below.

The preceding discussion is based on the assumptions that our general partner maintains its two percent general partner interest and that we do not issue additional classes of equity securities.

General Partner Interest and Incentive Distribution Rights

Our partnership agreement provides that our general partner was initially entitled to two percent of all distributions that we make prior to our liquidation. Our general partner has the right, but not the

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obligation, to contribute a proportionate amount of capital to us to maintain its two percent general partner interest if we issue additional units. Our general partner's two percent interest, and the percentage of our cash distributions to which it is entitled, will be proportionately reduced if we issue additional units in the future and our general partner does not contribute a proportionate amount of capital to us in order to maintain its two percent general partner interest. Our general partner is entitled to make a capital contribution in order to maintain its two percent general partner interest in the form of the contribution to us of common units based on the current market value of the contributed common units.

Incentive distribution rights represent the right to receive an increasing percentage (13 percent, 23 percent and 48 percent) of quarterly distributions of available cash from operating surplus after the minimum quarterly distribution and the target distribution levels have been achieved. Our general partner currently holds the incentive distribution rights, but may transfer these rights separately from its general partner interest, subject to restrictions in the partnership agreement.

The following discussion assumes that the general partner maintains its two percent general partner interest and continues to own the incentive distribution rights.

If for any quarter:

•: we have distributed available cash from operating surplus to the common units in an amount equal to the minimum quarterly distribution; and
•: we have distributed available cash from operating surplus on outstanding common units in an amount necessary to eliminate any cumulative arrearages in payment of the minimum quarterly distribution;

then, our partnership agreement requires that we distribute any additional available cash from operating surplus for that quarter among the unitholders and the general partner in the following manner:

•: first, 98 percent to all unitholders, pro rata, and two percent to the general partner, until each unitholder receives a total of $0.33063 per unit for that quarter (the "first target distribution");
•: second, 85 percent to all unitholders, pro rata, and 15 percent to the general partner, until each unitholder receives a total of $0.35938 per unit for that quarter (the "second target distribution");
•: third, 75 percent to all unitholders, pro rata, and 25 percent to the general partner, until each unitholder receives a total of $0.43125 per unit for that quarter (the "third target distribution"); and
•: thereafter, 50 percent to all unitholders, pro rata, and 50 percent to the general partner.

Percentage Allocations of Available Cash from Operating Surplus

The following table illustrates the percentage allocations of available cash from operating surplus between the unitholders and our general partner based on the specified target distribution levels. The amounts set forth under "Marginal Percentage Interest in Distribution" are the percentage interests of our general partner and the unitholders in any available cash from operating surplus we distribute up to and including the corresponding amount in the column "Total Quarterly Distribution per Unit Target Amount," until available cash from operating surplus we distribute reaches the next target distribution level, if any. The percentage interests shown for the unitholders and the general partner for the minimum quarterly distribution are also applicable to quarterly distribution amounts that are less than the minimum quarterly distribution. The percentage interests set forth below for our general partner include its two percent general partner interest and assume our general partner has contributed any

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additional capital to maintain its two percent general partner interest and has not transferred its incentive distribution rights.

		Marginal Percentage Interest in Distribution

	Total Quarterly Distribution per Unit Target Amount	Unitholders			General Partner
Minimum Quarterly Distribution	$0.28750		98	%		2	%
First Target Distribution	above $0.28750 up to $0.33063		98	%		2	%
Second Target Distribution	above $0.33063		85	%		15	%
	up to $0.35938
Third Target Distribution	above $0.35938		75	%		25	%
	up to $0.43125
Thereafter	above $0.43125		50	%		50	%

General Partner's Right to Reset Incentive Distribution Levels

Our general partner, as the holder of our incentive distribution rights, has the right under our partnership agreement to elect to relinquish the right to receive incentive distribution payments based on the initial cash target distribution levels and to reset, at higher levels, the minimum quarterly distribution amount and cash target distribution levels upon which the incentive distribution payments to our general partner would be set. Our general partner's right to reset the minimum quarterly distribution amount and the target distribution levels upon which the incentive distributions payable to our general partner are based may be exercised, without approval of our unitholders or the conflicts committee of our general partner, at any time when there are no subordinated units outstanding and we have made cash distributions to the holders of the incentive distribution rights at the highest level of incentive distribution for each of the prior four consecutive fiscal quarters. The reset minimum quarterly distribution amount and target distribution levels will be higher than the minimum quarterly distribution amount and the target distribution levels prior to the reset such that our general partner will not receive any incentive distributions under the reset target distribution levels until cash distributions per unit following this event increase as described below. In April 2012, the conditions were met which entitled our general partner to reset the minimum quarterly distribution amount and the target distribution levels upon which the incentive distributions payable to our general partner are set. The reset election has not been made, however we anticipate that our general partner would exercise this reset right in order to facilitate acquisitions or internal growth projects that would otherwise not be sufficiently accretive to cash distributions per common unit, taking into account the existing levels of incentive distribution payments being made to our general partner.

In connection with the resetting of the minimum quarterly distribution amount and the target distribution levels and the corresponding relinquishment by our general partner of incentive distribution payments based on the target cash distributions prior to the reset, our general partner will be entitled to receive a number of newly issued Class B common units and general partner units based on a predetermined formula described below that takes into account the "cash parity" value of the average cash distributions related to the incentive distribution rights received by our general partner for the two quarters prior to the reset event as compared to the average cash distributions per common unit during this period.

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The number of Class B common units that our general partner would be entitled to receive from us in connection with a resetting of the minimum quarterly distribution amount and the target distribution levels then in effect would be equal to (x) the average amount of cash distributions received by our general partner in respect of its incentive distribution rights during the two consecutive fiscal quarters ended immediately prior to the date of such reset election divided by (y) the average of the amount of cash distributed per common unit during each of these two quarters. Each Class B common unit will be convertible into one common unit at the election of the holder of the Class B common unit at any time following the first anniversary of the issuance of these Class B common units. The issuance of the Class B common units will be conditioned upon approval of the listing or admission for trading of the common units into which the Class B common units are convertible by the national securities exchange on which the common units are then listed or admitted for trading. Each Class B common unit will receive the same level of distribution as a common unit on a pari passu basis with other unitholders. Our general partner will also receive from us an additional amount of general partner units in order to maintain the general partner's ownership interest in us relative to the issuance of the common units. As the reset election has not been made, no Class B units have been issued.

Following a reset election by our general partner, the minimum quarterly distribution amount will be reset to an amount equal to the average cash distribution amount per common unit for the two fiscal quarters immediately preceding the reset election (such amount is referred to as the "reset minimum quarterly distribution") and the target distribution levels will be reset to be correspondingly higher such that we would distribute all of our available cash from operating surplus for each quarter thereafter as follows:

•: first, 98 percent to all unitholders, pro rata, and two percent to the general partner, until each unitholder receives an amount equal to 115 percent of the reset minimum quarter distribution for that quarter;
•: second, 85 percent to all unitholders, pro rata, and 15 percent to the general partner, until each unitholder receives an amount per unit equal to 125 percent of the reset minimum quarterly distribution for that quarter;
•: third, 75 percent to all unitholders, pro rata, and 25 percent to the general partner, until each unitholder receives an amount per unit equal to 150 percent of the reset minimum quarterly distribution for that quarter; and
•: thereafter, 50 percent to all unitholders, pro rata, and 50 percent to the general partner.

The following table illustrates the percentage allocation of available cash from operating surplus between the unitholders and our general partner at various cash distribution levels pursuant to the cash distribution provision of our partnership agreement as well as following a hypothetical reset of the minimum quarterly distribution and target distribution levels based on the assumption that the average

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quarterly cash distribution amount per common unit during the two fiscal quarters immediately preceding the reset election was $0.60.

			Marginal Percentage Interest in Distribution

	Quarterly Distribution per Unit Prior to Reset		Marginal Percentage Interest in Distribution						Quarterly Distribution per Unit following Hypothetical Reset
	Quarterly Distribution per Unit Prior to Reset		Unitholders			General Partner
Minimum Quarterly Distribution		$0.28750		98	%		2	%		$0.60000
First Target Distribution		above $0.28750		98	%		2	%		above $0.60000
		up to $0.33063								up to $0.69000
Second Target Distribution		above $0.33063		85	%		15	%		above $0.69000
		up to $0.35938								up to $0.75000	(1)
Third Target Distribution		above $0.35938		75	%		25	%		above $0.75000
		up to $0.43125								up to $0.90000	(2)
Thereafter		above $0.43125		50	%		50	%		above $0.90000	(3)

(1): This amount is 115% of the hypothetical reset minimum quarterly distribution.
(2): This amount is 125% of the hypothetical reset minimum quarterly distribution.
(3): This amount is 150% of the hypothetical reset minimum quarterly distribution.

The following table illustrates the total amount of available cash from operating surplus that would be distributed to the unitholders and the general partner, including in respect of incentive distribution rights, or IDRs, based on an average of the amounts distributed per quarter for the two quarters immediately prior to the reset. The following table assumes that immediately prior to the reset there are 215,789,325 common units and 4,403,765 general partner units, representing a two percent general partner interest, outstanding, and that the average distribution to each common unit is $0.60 for the two quarters prior to the reset. The assumed number of outstanding units no additional unit issuances.

				General Partner Cash Distributions Prior to Reset

		Common Unitholders Cash Distributions Prior to Reset
	Quarterly Distribution per Unit Prior to Reset
	Quarterly Distribution per Unit Prior to Reset			Class B Units		2% General Partner Interest		IDRs		Total		Total Distributions
Minimum Quarterly Distribution	$0.28750	$	62,039,431	$	—	$	1,266,111	$	—	$	1,266,111	$	63,305,542
First Target Distribution	above $0.28750 up to $0.33063		9,305,915		—		189,917		—		189,917		9,495,831
Second Target Distribution	above $0.33063 up to $0.35938		6,203,943		—		145,975		948,838		1,094,813		7,298,757
Third Target Distribution	above $0.35938 up to $0.43125		15,509,858		—		413,596		4,756,356		5,169,953		20,679,810
Thereafter	above $0.43125		36,414,449		—		1,456,578		34,957,871		36,414,449		72,828,897

		$	129,473,595	$	—	$	3,472,177	$	40,663,065	$	44,135,242	$	173,608,837

The following table illustrates the total amount of available cash from operating surplus that would be distributed to the unitholders and the general partner, including in respect of IDRs, with respect to the quarter in which the reset occurs. The table reflects that as a result of the reset there are 215,789,325 common units, 67,771,776 Class B common units issued as a result of the reset and 5,786,961 general partner units outstanding, and that the average distribution to each common unit is $0.60000 for the two quarters prior to the reset. The number of Class B common units issued as a result of the reset was calculated by dividing (x) $40,663,065 as the average of the amounts received by the general partner in respect of its incentive distribution rights, or IDRs, for the two quarters prior to the reset as shown in the table above by (y) the $0.60000 of available cash from operating surplus

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distributed to each common unit as the average distributed per common unit for the two quarters prior to the reset.

				General Partner Cash Distributions After Reset

	Quarterly Distribution per Unit After Reset	Common Unitholders Cash Distributions After Reset		Class B Units Issued as a Result of the Reset		2% General Partner Interest		IDRs		Total		Total Distributions
Minimum Quarterly Distribution	$0.60000	$	129,473,595	$	40,663,066	$	3,472,177	$	—	$	44,135,242	$	173,608,837
First Target Distribution	above $0.60000 up to $0.69000		—		—		—		—		—		—
Second Target Distribution	above $0.69000 up to $0.75000		—		—		—		—		—		—
Third Target Distribution	above $0.75000 up to $0.90000		—		—		—		—		—		—
Thereafter	above $0.90000		—		—		—		—		—		—

		$	129,473,595	$	40,663,066	$	3,472,177	$	—	$	44,135,242	$	173,608,837

Our general partner will be entitled to cause the minimum quarterly distribution amount and the target distribution levels to be reset on more than one occasion, provided that it may not make a reset election except at a time when it has received incentive distributions for the prior four consecutive fiscal quarters based on the highest level of incentive distributions that it is entitled to receive under our partnership agreement.

Distributions from Capital Surplus

How Distributions from Capital Surplus Will Be Made

Our partnership agreement requires that we make distributions of available cash from capital surplus, if any, in the following manner:

•: first, 98 percent to all unitholders, pro rata, and two percent to the general partner, until we distribute for each common unit an amount of available cash from capital surplus equal to the initial public offering price;
•: second, 98 percent to the common unitholders, pro rata, and two percent to the general partner, until we distribute for each common unit an amount of available cash from capital surplus equal to any unpaid arrearages in payment of the minimum quarterly distribution on the common units; and
•: thereafter, we will make all distributions of available cash from capital surplus as if they were from operating surplus.

Effect of a Distribution from Capital Surplus

Our partnership agreement treats a distribution of capital surplus as the repayment of the initial unit price from the initial public offering, which is a return of capital. The initial public offering price less any distributions of capital surplus per unit is referred to as the "unrecovered initial unit price." Each time a distribution of capital surplus is made, the minimum quarterly distribution and the target distribution levels will be reduced in the same proportion as the corresponding reduction in the unrecovered initial unit price. Because distributions of capital surplus will reduce the minimum quarterly distribution, after any of these distributions are made, it may be easier for the general partner to receive incentive distributions. However, any distribution of capital surplus before the unrecovered initial unit price is reduced to zero cannot be applied to the payment of the minimum quarterly distribution or any arrearages.

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Once we distribute capital surplus on a unit in an amount equal to the initial unit price, our partnership agreement specifies that the minimum quarterly distribution and the target distribution levels will be reduced to zero. Our partnership agreement specifies that we then make all future distributions from operating surplus, with 50 percent being paid to the holders of units and 50 percent to the general partner. The percentage interests shown for our general partner include its two percent general partner interest and assume the general partner has not transferred the incentive distribution rights.

Adjustment to the Minimum Quarterly Distribution and Target Distribution Levels

In addition to adjusting the minimum quarterly distribution and target distribution levels to reflect a distribution of capital surplus, if we combine our units into fewer units or subdivide our units into a greater number of units, our partnership agreement specifies that the following items will be proportionately adjusted:

•: the minimum quarterly distribution;
•: target distribution levels;
•: the unrecovered initial unit price; and
•: the number of general partner units.

For example, if a two-for-one split of the common units should occur, the minimum quarterly distribution, the target distribution levels and the unrecovered initial unit price would each be reduced to 50 percent of its initial level. The two-for-one split would also result in the number of general partner units evidencing the general partner interest being doubled. Our partnership agreement provides that we not make any adjustment by reason of the issuance of additional units for cash or property.

In addition, if legislation is enacted or if existing law is modified or interpreted by a governmental taxing authority, so that we become taxable as a corporation or otherwise subject to taxation as an entity for federal, state or local income tax purposes, our partnership agreement specifies that the general partner may reduce the minimum quarterly distribution and the target distribution levels for each quarter by multiplying each distribution level by a fraction, the numerator of which is available cash for that quarter and the denominator of which is the sum of available cash for that quarter plus the general partner's estimate of our aggregate liability for the quarter for such income taxes payable by reason of such legislation or interpretation. To the extent that the actual tax liability differs from the estimated tax liability for any quarter, the difference will be accounted for in subsequent quarters.

Distributions of Cash Upon Liquidation

General

If we dissolve in accordance with the partnership agreement, we will sell or otherwise dispose of our assets in a process called liquidation. We will first apply the proceeds of liquidation to the payment of our creditors. We will distribute any remaining proceeds to the unitholders and the general partner, in accordance with their capital account balances, as adjusted to reflect any gain or loss upon the sale or other disposition of our assets in liquidation.

The allocations of gain and loss upon liquidation are intended, to the extent possible, to entitle the holders of outstanding common units to receive their unrecovered initial unit price plus the minimum quarterly distribution for the quarter during which liquidation occurs plus any unpaid arrearages in payment of the minimum quarterly distribution on the common units. However, there may not be sufficient gain upon our liquidation to enable the holders of common units to fully recover all of these

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amounts. Any further net gain recognized upon liquidation will be allocated in a manner that takes into account the incentive distribution rights of the general partner.

Manner of Adjustments for Gain

The manner of the adjustment for gain is set forth in the partnership agreement. We will allocate any gain to the partners in the following manner:

•: first, to the general partner and the holders of units who have negative balances in their capital accounts to the extent of and in proportion to those negative balances;
•: second, 98 percent to the common unitholders, pro rata, and two percent to the general partner, until the capital account for each common unit is equal to the sum of: (1) the unrecovered initial unit price; and (2) the amount of the minimum quarterly distribution for the quarter during which our liquidation occurs;
•: third, 98 percent to the Class B common unitholders, pro rata, and two percent to the general partner, until the capital account for each Class B common unit is equal to the sum of: (1) the unrecovered initial unit price; and (2) the amount for the minimum quarterly distribution for the quarter during which our liquidation occurs;
•: fourth, 98 percent to all unitholders, pro rata, and two percent to the general partner, until we allocate under this paragraph an amount per unit equal to: (1) the sum of the excess of the first target distribution per unit over the minimum quarterly distribution per unit for each quarter of our existence; less (2) the cumulative amount per unit of any distributions of available cash from operating surplus in excess of the minimum quarterly distribution per unit that we distributed 98 percent to the unitholders, pro rata, and two percent to the general partner, for each quarter of our existence;
•: fifth, 85 percent to all unitholders, pro rata, and 15 percent to the general partner, until we allocate under this paragraph an amount per unit equal to: (1) the sum of the excess of the second target distribution per unit over the first target distribution per unit for each quarter of our existence; less (2) the cumulative amount per unit of any distributions of available cash from operating surplus in excess of the first target distribution per unit that we distributed 85 percent to the unitholders, pro rata, and 15 percent to the general partner for each quarter of our existence;
•: sixth, 75 percent to all unitholders, pro rata, and 25 percent to the general partner, until we allocate under this paragraph an amount per unit equal to: (1) the sum of the excess of the third target distribution per unit over the second target distribution per unit for each quarter of our existence; less (2) the cumulative amount per unit of any distributions of available cash from operating surplus in excess of the second target distribution per unit that we distributed 75 percent to the unitholders, pro rata, and 25 percent to the general partner for each quarter of our existence; and
•: thereafter, 50 percent to all unitholders, pro rata, and 50 percent to the general partner.

The percentage interests set forth above for our general partner include its two percent general partner interest and assume the general partner has not transferred the incentive distribution rights.

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Manner of Adjustments for Losses

We will generally allocate any loss to the general partner and the unitholders in the following manner:

•: first, 98 percent to the holders of Class B common units in proportion to the positive balances in their capital accounts and two percent to the general partner, until the capital accounts of the Class B common unitholders have been reduced to zero;
•: second, 98 percent to the holders of common units in proportion to the positive balances in their capital accounts and two percent to the general partner, until the capital accounts of the common unitholders have been reduced to zero; and
•: thereafter, 100 percent to the general partner.

Adjustments to Capital Accounts

Our partnership agreement requires that we make adjustments to capital accounts upon the issuance of additional units. In this regard, our partnership agreement specifies that we allocate any unrealized and, for tax purposes, unrecognized gain or loss resulting from the adjustments to the unitholders and the general partner in the same manner as we allocate gain or loss upon liquidation. In the event that we make positive adjustments to the capital accounts upon the issuance of additional units, our partnership agreement requires that we allocate any later negative adjustments to the capital accounts resulting from the issuance of additional units or upon our liquidation in a manner which results, to the extent possible, in the general partner's capital account balances equaling the amount which they would have been if no earlier positive adjustments to the capital accounts had been made.

Transfer Agent and Registrar

Computershare Trust Company, N.A. serves as registrar and transfer agent for the common units.

The transfer agent may resign, by notice to us, or be removed by us. The resignation or removal of the transfer agent will become effective upon our appointment of a successor transfer agent and registrar and its acceptance of the appointment. If no successor has been appointed and has accepted the appointment within 30 days after notice of the resignation or removal, our general partner may act as the transfer agent and registrar until a successor is appointed.

Transfer of Common Units

Any transfers of a common unit will not be recorded by the transfer agent or recognized by us unless the transferee executes and delivers a properly completed transfer application. By executing and delivering a transfer application, the transferee of common units:

•: becomes the record holder of the common units and is an assignee until admitted into our partnership as a substituted limited partner;
•: automatically requests admission as a substituted limited partner in our partnership;
•: executes and agrees to be bound by the terms and conditions of our partnership agreement;
•: represents that the transferee has the capacity, power and authority to enter into our partnership agreement;
•: grants powers of attorney to the officers of our general partner and any liquidator of us as specified in our partnership agreement;

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gives the consents, covenants, representations and approvals contained in our partnership agreement; and certifies:

•: that the transferee is an individual or is an entity subject to U.S. federal income taxation on the income generated by us; or
•: that, if the transferee is an entity not subject to U.S. federal income taxation on the income generated by us, as in the case, for example, of a mutual fund taxed as a regulated investment company or a partnership, all the entity's owners are subject to U.S. federal income taxation on the income generated by us.

An assignee will become a substituted limited partner of our partnership for the transferred common units automatically upon the recording of the transfer on our books and records. Our general partner will cause any unrecorded transfers for which a properly completed and duly executed transfer application has been received to be recorded on our books and records no less frequently than quarterly.

A transferee's broker, agent or nominee may, but is not obligated to, complete, execute and deliver a transfer application. We are entitled to treat the nominee holder of a common unit as the absolute owner. In that case, the beneficial holder's rights are limited solely to those that it has against the nominee holder as a result of any agreement between the beneficial owner and the nominee holder.

Common units are securities and are transferable according to the laws governing transfer of securities. In addition to other rights acquired upon transfer, the transferor gives the transferee the right to request admission as a substituted limited partner in our partnership for the transferred common units. A purchaser or transferee of common units who does not execute and deliver a properly completed transfer application obtains only:

•: the right to assign the common unit to a purchaser or other transferee; and
•: the right to transfer the right to seek admission as a substituted limited partner in our partnership for the transferred common units.

Thus, a purchaser or transferee of common units who does not execute and deliver a properly completed transfer application:

•: will not receive cash distributions;
•: will not be allocated any of our income, gain, deduction, losses or credits for federal income tax or other tax purposes;
•: may not receive some federal income tax information or reports furnished to record holders of common units; and
•: will not have voting rights;

unless the common units are held in a nominee or "street name" account and the nominee or broker has executed and delivered a transfer application and certification as to itself and any beneficial holders.

The transferor of common units has a duty to provide the transferee with all information that may be necessary to transfer the common units. The transferor does not have a duty to ensure the execution of the transfer application by the transferee and has no liability or responsibility if the transferee neglects or chooses not to execute and deliver a properly completed transfer application to the transfer agent. Please read "Material Provisions of Our Partnership Agreement—Status as Limited Partner."

Until a common unit has been transferred on our books, we and the transfer agent may treat the record holder of the unit as the absolute owner for all purposes, except as otherwise required by law or stock exchange regulations.

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MATERIAL PROVISIONS OF OUR PARTNERSHIP AGREEMENT

The following is a summary of the material provisions of our partnership agreement. Our partnership agreement is incorporated by reference as an exhibit to the registration statement of which this prospectus constitutes a part. We will provide prospective investors with a copy of our partnership agreement upon request at no charge.

We summarize the following provisions of our partnership agreement elsewhere in this prospectus:

•: with regard to distributions of available cash, please read "Description of the Common Units—Distributions of Available Cash";
•: with regard to the fiduciary duties of our general partner, please read "Modification of Fiduciary Duties Owed to the Limited Partners";
•: with regard to the transfer of common units, please read "Description of the Common Units—Transfer of Common Units"; and
•: with regard to allocations of taxable income and taxable loss, please read "Material Tax Consequences."

Organization and Duration

Our partnership was organized August 1, 2007 and will have a perpetual existence.

Purpose

Our purpose under the partnership agreement is limited to any business activity that is approved by our general partner and that lawfully may be conducted by a limited partnership organized under Delaware law; provided that our general partner shall not cause us to engage, directly or indirectly, in any business activity that our general partner determines would cause us to be treated as an association taxable as a corporation or otherwise taxable as an entity for federal income tax purposes.

Although our general partner has the ability to cause us and our subsidiaries to engage in activities other than the business of gathering, transporting, processing and storing natural gas, our general partner has no current plans to do so and may decline to do so free of any fiduciary duty or obligation whatsoever to us or the limited partners, including any duty to act in good faith or in the best interests of us or the limited partners. Our general partner is authorized in general to perform all acts it determines to be necessary or appropriate to carry out our purposes and to conduct our business.

Power of Attorney

Each limited partner, and each person who acquires a common unit from a unitholder, by accepting the common unit, automatically grants to our general partner and, if appointed, a liquidator, a power of attorney to, among other things, execute and file documents required for our qualification, continuance or dissolution. The power of attorney also grants our general partner the authority to amend, and to make consents and waivers under, our partnership agreement.

Cash Distributions

Our partnership agreement specifies the manner in which we make cash distributions to holders of our common units and other partnership securities as well as to our general partner in respect of its general partner interest and its incentive distribution rights. For a description of these cash distribution provisions, please read "Description of the Common Units—Distributions of Available Cash."

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Capital Contributions

Unitholders are not obligated to make additional capital contributions, except as described below under "—Limited Liability."

For a discussion of our general partner's right to contribute capital to maintain its two percent general partner interest if we issue additional units, please read "—Issuance of Additional Securities."

Voting Rights

The following is a summary of the unitholder vote required for the matters specified below. Matters requiring the approval of a "unit majority" require the approval of a majority of the common units and Class B common units, if any, voting as a single class.

In voting their common units and Class B common units, our general partner and its affiliates will have no fiduciary duty or obligation whatsoever to us or the limited partners, including any duty to act in good faith or in the best interests of us or the limited partners.


Issuance of additional units		No approval right.
Amendment of the partnership agreement		Certain amendments may be made by our general partner without the approval of our unitholders. Other amendments generally require the approval of a unit majority. Please read "—Amendment of the Partnership Agreement."
Merger of our partnership or the sale of all or substantially all of our assets		Unit majority in certain circumstances. Please read "—Merger, Consolidation, Conversion, Sale or Other Disposition of Assets."
Dissolution of our partnership		Unit majority. Please read "—Termination and Dissolution."
Continuation of our business upon dissolution		Unit majority. Please read "—Termination and Dissolution."
Withdrawal of our general partner		Under most circumstances, the approval of a majority of the common units, excluding common units held by our general partner and its affiliates, is required for the withdrawal of our general partner prior to December 31, 2017 in a manner that would cause a dissolution of our partnership. Please read "—Withdrawal or Removal of the General Partner."
Removal of the general partner		Not less than 66²/3% of our outstanding units, voting as a single class, including units held by our general partner and its affiliates. Please read "—Withdrawal or Removal of the General Partner."

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Transfer of the general partner interest		Our general partner may transfer all, but not less than all, of its general partner interest in us without a vote of our unitholders to an affiliate or another person in connection with its merger or consolidation with or into, or sale of all or substantially all of its assets to, such person. The approval of a majority of the common units, excluding common units held by the general partner and its affiliates, is required in other circumstances for a transfer of the general partner interest to a third party prior to December 31, 2017. Please read "—Transfer of General Partner Interest."
Transfer of incentive distribution rights		Our general partner may transfer any or all of the incentive distribution rights without a vote of our unitholders to an affiliate or another person as part of our general partner's merger or consolidation with or into, or sale of all or substantially all of its assets or the sale of all of the ownership interests in such holder to, such person. The approval of a majority of the common units, excluding common units held by the general partner and its affiliates, is required in other circumstances for a transfer of the incentive distribution rights to a third party prior to December 31, 2017. Please read "—Transfer of Incentive Distribution Rights."
Transfer of ownership interests in our general partner		No approval required at any time. Please read "—Transfer of Ownership Interests in the General Partner."

Limited Liability

Assuming that a limited partner does not participate in the control of our business within the meaning of the Delaware Revised Uniform Limited Partnership Act, or the Delaware Act, and that he otherwise acts in conformity with the provisions of the partnership agreement, his liability under the Delaware Act will be limited, subject to possible exceptions, to the amount of capital he is obligated to contribute to us for his common units plus his share of any undistributed profits and assets. If it were determined, however, that the right, or exercise of the right, by the limited partners as a group:

•: to remove or replace the general partner;
•: to approve some amendments to the partnership agreement; or
•: to take other action under the partnership agreement;

constituted "participation in the control" of our business for the purposes of the Delaware Act, then the limited partners could be held personally liable for our obligations under the laws of Delaware, to the same extent as the general partner. This liability would extend to persons who transact business with us who reasonably believe that the limited partner is a general partner. Neither the partnership agreement nor the Delaware Act specifically provides for legal recourse against the general partner if a limited partner were to lose limited liability through any fault of the general partner. While this does not mean that a limited partner could not seek legal recourse, we know of no precedent for this type of a claim in Delaware case law.

Under the Delaware Act, a limited partnership may not make a distribution to a partner if, after the distribution, all liabilities of the limited partnership, other than liabilities to partners on account of their limited partner interests and liabilities for which the recourse of creditors is limited to specific property of the partnership, would exceed the fair value of the assets of the limited partnership. For

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the purpose of determining the fair value of the assets of a limited partnership, the Delaware 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 non-recourse liability. The Delaware Act provides that a limited partner who receives a distribution and knew at the time of the distribution that the distribution was in violation of the Delaware Act shall be liable to the limited partnership for the amount of the distribution for three years. Under the Delaware Act, a substituted limited partner of a limited partnership is liable for the obligations of his assignor to make contributions to the partnership, except that such person is not obligated for liabilities unknown to him at the time he became a limited partner and that could not be ascertained from the partnership agreement.

Our subsidiaries conduct business in sixteen states and we may have subsidiaries that conduct business in other states in the future. Maintenance of our limited liability as a member of the operating company may require compliance with legal requirements in the jurisdictions in which the operating company conducts business, including qualifying our subsidiaries to do business there.

Limitations on the liability of limited partners for the obligations of a limited partner have not been clearly established in many jurisdictions. If, by virtue of our membership interest in our operating company or otherwise, it were determined that we were conducting business in any state without compliance with the applicable limited partnership or limited liability company statute, or that the right or exercise of the right by the limited partners as a group to remove or replace the general partner, to approve some amendments to the partnership agreement, or to take other action under the partnership agreement constituted "participation in the control" of our business for purposes of the statutes of any relevant jurisdiction, then the limited partners could be held personally liable for our obligations under the law of that jurisdiction to the same extent as the general partner under the circumstances. We have and will continue to operate in a manner that the general partner considers reasonable and necessary or appropriate to preserve the limited liability of the limited partners.

Issuance of Additional Securities

Our partnership agreement authorizes us to issue an unlimited number of additional partnership securities for the consideration and on the terms and conditions determined by our general partner without the approval of the unitholders.

It is possible that we will fund acquisitions through the issuance of additional common units or other partnership securities. Holders of any additional common units we issue will be entitled to share equally with the then-existing holders of common units in our distributions of available cash. In addition, the issuance of additional common units or other partnership securities may dilute the value of the interests of the then-existing holders of common units in our net assets.

In accordance with Delaware law and the provisions of our partnership agreement, we may also issue additional partnership securities that, as determined by our general partner, may have special voting rights to which the common units are not entitled. In addition, our partnership agreement does not prohibit the issuance by our subsidiaries of equity securities, which may effectively rank senior as to distributions or in liquidation to the common units.

Upon issuance of additional partnership securities (other than the issuance of Class B common units in connection with a reset of the incentive distribution target levels or the issuance of partnership securities upon conversion of outstanding partnership securities), our general partner will be entitled, but not required, to make additional capital contributions to the extent necessary to maintain its two percent general partner interest in us. Our general partner's two percent interest in us will be reduced if we issue additional units in the future and our general partner does not contribute a proportionate amount of capital to us to maintain its two percent general partner interest. Moreover, our general partner will have the right, which it may from time to time assign in whole or in part to any of its

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affiliates, to purchase common units or other partnership securities whenever, and on the same terms that, we issue those securities to persons other than our general partner and its affiliates, to the extent necessary to maintain the percentage interest of the general partner and its affiliates, including such interest represented by common units, that existed immediately prior to each issuance. The holders of common units do not have preemptive rights to acquire additional common units or other partnership securities.

Amendment of the Partnership Agreement

General

Amendments to our partnership agreement may be proposed only by or with the consent of our general partner. However, our general partner has no duty or obligation to propose any amendment and may decline to do so free of any fiduciary duty or obligation whatsoever to us or the limited partners, including any duty to act in good faith or in the best interests of us or the limited partners. In order to adopt a proposed amendment, other than the amendments discussed below, our general partner is required to seek written approval of the holders of the number of units required to approve the amendment or call a meeting of the limited partners to consider and vote upon the proposed amendment. Except as described below, an amendment must be approved by a unit majority.

Prohibited Amendments

No amendment may be made that would:

•: enlarge the obligations of any limited partner without its consent, unless approved by at least a majority of the type or class of limited partner interests so affected; or
•: enlarge the obligations of, restrict in any way any action by or rights of, or reduce in any way the amounts distributable, reimbursable or otherwise payable by us to our general partner or any of its affiliates without the consent of our general partner, which consent may be given or withheld at its option.

The provision of our partnership agreement preventing the amendments having the effects described in any of the clauses above can be amended upon the approval of the holders of at least 90 percent of the outstanding units voting together as a single class (including units owned by our general partner and its affiliates). As of December 31, 2012, our general partner and its affiliates owned approximately 41 percent of the outstanding common units.

No Unitholder Approval

Our general partner may generally make amendments to our partnership agreement without the approval of any limited partner to reflect:

•: a change in our name, the location of our principal place of our business, our registered agent or our registered office;
•: the admission, substitution, withdrawal or removal of partners in accordance with our partnership agreement;
•: a change that our general partner determines to be necessary or appropriate to qualify or continue our qualification as a limited partnership or a partnership in which the limited partners have limited liability under the laws of any state or to ensure that neither we nor the operating company nor any of its subsidiaries will be treated as an association taxable as a corporation or otherwise taxed as an entity for federal income tax purposes;

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an amendment that is necessary, in the opinion of our counsel, to prevent us or our general partner or its directors, officers, agents or trustees from in any manner being subjected to the provisions of the Investment Company Act of 1940, the Investment Advisors Act of 1940, or "plan asset" regulations adopted under the Employee Retirement Income Security Act of 1974, or ERISA, whether or not substantially similar to plan asset regulations currently applied or proposed;

•

an amendment that our general partner determines to be necessary or appropriate for the authorization of additional partnership securities or rights to acquire partnership securities, including any amendment that our general partner determines is necessary or appropriate in connection with:

•: the adjustments of the minimum quarterly distribution, first target distribution, second target distribution and third target distribution in connection with the reset of our general partner's incentive distribution rights as described under "Description of the Common Units—Distributions of Available Cash—General Partner's Right to Reset Incentive Distribution Levels"; or
•: the implementation of the provisions relating to our general partner's right to reset its incentive distribution rights in exchange for Class B common units; and
•: any modification of the incentive distribution rights made in connection with the issuance of additional partnership securities or rights to acquire partnership securities, provided that, any such modifications and related issuance of partnership securities have received approval by a majority of the members of the conflicts committee of our general partner; any amendment expressly permitted in our partnership agreement to be made by our general partner acting alone;

•

any amendment expressly permitted in our partnership agreement to be made by our general partner acting alone;

•

an amendment effected, necessitated or contemplated by a merger agreement that has been approved under the terms of our partnership agreement;

•

any amendment that our general partner determines to be necessary or appropriate for the formation by us of, or our investment in, any corporation, partnership or other entity, as otherwise permitted by our partnership agreement;

•

a change in our fiscal year or taxable year and related changes;

•

conversions into, mergers with or conveyances to another limited liability entity that is newly formed and has no assets, liabilities or operations at the time of the conversion, merger or conveyance other than those it receives by way of the conversion, merger or conveyance; or

•

any other amendments substantially similar to any of the matters described in the clauses above.

In addition, our general partner may make amendments to our partnership agreement without the approval of any limited partner if our general partner determines that those amendments:

•: do not adversely affect in any material respect the limited partners considered as a whole or any particular class of limited partners;
•: are necessary or appropriate to satisfy any requirements, conditions or guidelines contained in any opinion, directive, order, ruling or regulation of any federal or state agency or judicial authority or contained in any federal or state statute;

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•: are necessary or appropriate to facilitate the trading of limited partner interests or to comply with any rule, regulation, guideline or requirement of any securities exchange on which the limited partner interests are or will be listed for trading;
•: are necessary or appropriate for any action taken by our general partner relating to splits or combinations of units under the provisions of our partnership agreement; or
•: are required to effect the intent expressed in this prospectus or the intent of the provisions of our partnership agreement or are otherwise contemplated by our partnership agreement.

Opinion of Counsel and Unitholder Approval

For amendments of the type not requiring unitholder approval, our general partner is not required to obtain an opinion of counsel that an amendment will not result in a loss of limited liability to the limited partners or result in our being treated as an entity for federal income tax purposes in connection with any of the amendments. No other amendments to our partnership agreement will become effective without the approval of holders of at least 90 percent of the outstanding units voting as a single class unless we first obtain an opinion of counsel to the effect that the amendment will not affect the limited liability under applicable law of any of our limited partners.

In addition to the above restrictions, any amendment that would have a material adverse effect on the rights or preferences of any type or class of outstanding units in relation to other classes of units requires the approval of at least a majority of the type or class of units so affected. Any amendment that reduces the voting percentage required to take any action is required to be approved by the affirmative vote of limited partners whose aggregate outstanding units constitute not less than the voting requirement sought to be reduced.

Merger, Consolidation, Conversion, Sale or Other Disposition of Assets

A merger, consolidation or conversion of us requires the prior consent of our general partner. However, our general partner has no duty or obligation to consent to any merger, consolidation or conversion and may decline to do so free of any fiduciary duty or obligation whatsoever to us or the limited partners, including any duty to act in good faith or in the best interest of us or the limited partners.

In addition, the partnership agreement generally prohibits our general partner without the prior approval of the holders of a unit majority, from causing us to, among other things, sell, exchange or otherwise dispose of all or substantially all of our assets in a single transaction or a series of related transactions, including by way of merger, consolidation or other combination, or approving on our behalf the sale, exchange or other disposition of all or substantially all of the assets of our subsidiaries. Our general partner may, however, mortgage, pledge, hypothecate or grant a security interest in all or substantially all of our assets without that approval. Our general partner may also sell all or substantially all of our assets under a foreclosure or other realization upon those encumbrances without that approval. Finally, our general partner may consummate any merger without the prior approval of our unitholders if we are the surviving entity in the transaction, our general partner has received an opinion of counsel regarding limited liability and tax matters, the transaction would not result in a material amendment to the partnership agreement, each of our units will be an identical unit of our partnership following the transaction, and the partnership securities to be issued do not exceed 20 percent of our outstanding partnership securities immediately prior to the transaction.

If the conditions specified in the partnership agreement are satisfied, our general partner may convert us or any of our subsidiaries into a new limited liability entity or merge us or any of our subsidiaries into, or convey all of our assets to, a newly formed entity if the sole purpose of that conversion, merger or conveyance is to effect a mere change in our legal form into another limited

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liability entity, our general partner has received an opinion of counsel regarding limited liability and tax matters, and the governing instruments of the new entity provide the limited partners and the general partner with the same rights and obligations as contained in the partnership agreement. The unitholders are not entitled to dissenters' rights of appraisal under the partnership agreement or applicable Delaware law in the event of a conversion, merger or consolidation, a sale of substantially all of our assets or any other similar transaction or event.

Termination and Dissolution

We will continue as a limited partnership until terminated under our partnership agreement. We will dissolve upon:

•: the election of our general partner to dissolve us, if approved by the holders of units representing a unit majority;
•: there being no limited partners, unless we are continued without dissolution in accordance with applicable Delaware law;
•: the entry of a decree of judicial dissolution of our partnership; or
•: the withdrawal or removal of our general partner or any other event that results in its ceasing to be our general partner other than by reason of a transfer of its general partner interest in accordance with our partnership agreement or withdrawal or removal following approval and admission of a successor.

Upon a dissolution under the last clause above, the holders of a unit majority may also elect, within specific time limitations, to continue our business on the same terms and conditions described in our partnership agreement by appointing as a successor general partner an entity approved by the holders of units representing a unit majority, subject to our receipt of an opinion of counsel to the effect that:

•: the action would not result in the loss of limited liability of any limited partner; and
•: neither our partnership, our operating company nor any of our other subsidiaries would be treated as an association taxable as a corporation or otherwise be taxable as an entity for federal income tax purposes upon the exercise of that right to continue.

Liquidation and Distribution of Proceeds

Upon our dissolution, unless we are continued as a new limited partnership, the liquidator authorized to wind up our affairs will, acting with all of the powers of our general partner that are necessary or appropriate to liquidate our assets and apply the proceeds of the liquidation as described in "Description of the Common Units—Distributions of Available Cash—Distributions of Cash Upon Liquidation." The liquidator may defer liquidation or distribution of our assets for a reasonable period of time or distribute assets to partners in kind if it determines that a sale would be impractical or would cause undue loss to our partners.

Withdrawal or Removal of the General Partner

Except as described below, our general partner has agreed not to withdraw voluntarily as our general partner prior to December 31, 2017 without obtaining the approval of the holders of at least a majority of the outstanding common units, excluding common units held by the general partner and its affiliates, and furnishing an opinion of counsel regarding limited liability and tax matters. On or after December 31, 2017, our general partner may withdraw as general partner without first obtaining approval of any unitholder by giving 90 days' written notice, and that withdrawal will not constitute a violation of our partnership agreement. Notwithstanding the information above, our general partner

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may withdraw without unitholder approval upon 90 days' notice to the limited partners if at least 50 percent of the outstanding common units are held or controlled by one person and its affiliates other than the general partner and its affiliates. In addition, the partnership agreement permits our general partner in some instances to sell or otherwise transfer all of its general partner interest in us without the approval of the unitholders. Please read "—Transfer of General Partner Units" and "—Transfer of Incentive Distribution Rights."

Upon withdrawal of our general partner under any circumstances, other than as a result of a transfer by our general partner of all or a part of its general partner interest in us, the holders of a unit majority, voting as separate classes, may select a successor to that withdrawing general partner. If a successor is not elected, or is elected but an opinion of counsel regarding limited liability and tax matters cannot be obtained, we will be dissolved, wound up and liquidated, unless within a specified period after that withdrawal, the holders of a unit majority agree in writing to continue our business and to appoint a successor general partner. Please read "—Termination and Dissolution."

Our general partner may not be removed unless that removal is approved by the vote of the holders of not less than 66²/3 percent of the outstanding units, voting together as a single class, including units held by our general partner and its affiliates, and we receive an opinion of counsel regarding limited liability and tax matters. Any removal of our general partner is also subject to the approval of a successor general partner by the vote of the holders of a majority of the outstanding common units and Class B common units, if any. The ownership of more than 33¹/3 percent of the outstanding units by our general partner and its affiliates would give them the practical ability to prevent our general partner's removal. As of December 31, 2012, our general partner and its affiliates owned approximately 41 percent of the outstanding common units.

Our partnership agreement also provides that if our general partner is removed as our general partner under circumstances where cause does not exist and units held by the general partner and its affiliates are not voted in favor of that removal:

•: any existing arrearages in payment of the minimum quarterly distribution on the common units will be extinguished; and
•: our general partner will have the right to convert its general partner interest and its incentive distribution rights into common units or to receive cash in exchange for those interests based on the fair market value of those interests at that time.

In the event of removal of a general partner under circumstances where cause exists or withdrawal of a general partner where that withdrawal violates our partnership agreement, a successor general partner will have the option to purchase the general partner interest and incentive distribution rights of the departing general partner for a cash payment equal to the fair market value of those interests. Under all other circumstances where a general partner withdraws or is removed by the limited partners, the departing general partner will have the option to require the successor general partner to purchase the general partner interest of the departing general partner and its incentive distribution rights for fair market value. In each case, this fair market value will be determined by agreement between the departing general partner and the successor general partner. If no agreement is reached, an independent investment banking firm or other independent expert selected by the departing general partner and the successor general partner will determine the fair market value. Or, if the departing general partner and the successor general partner cannot agree upon an expert, then an expert chosen by agreement of the experts selected by each of them will determine the fair market value.

If the option described above is not exercised by either the departing general partner or the successor general partner, the departing general partner's general partner interest and its incentive distribution rights will automatically convert into common units equal to the fair market value of those interests as determined by an investment banking firm or other independent expert selected in the manner described in the preceding paragraph.

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In addition, we will be required to reimburse the departing general partner for all amounts due the departing general partner, including, without limitation, all employee-related liabilities, including severance liabilities, incurred for the termination of any employees employed by the departing general partner or its affiliates for our benefit.

Transfer of General Partner Interest

Except for transfer by our general partner of all, but not less than all, of its general partner interest in us to:

•: an affiliate of our general partner (other than an individual); or
•: another entity as part of the merger or consolidation of our general partner with or into another entity or the transfer by our general partner of all or substantially all of its assets to another entity, our general partner may not transfer all or any of its general partner units to another person prior to December 31, 2017 without the approval of the holders of at least a majority of the outstanding common units, excluding common units held by our general partner and its affiliates. As a condition of this transfer, the transferee must assume, among other things, the rights and duties of our general partner, agree to be bound by the provisions of our partnership agreement, and furnish an opinion of counsel regarding limited liability and tax matters.

Our general partner and its affiliates may, at any time, transfer units to one or more persons, without unitholder approval.

Transfer of Ownership Interests in the General Partner

At any time, KMI and its affiliates may, directly or indirectly, sell or transfer all or part of their membership interest in our general partner to an affiliate or third party without the approval of our unitholders.

Transfer of Incentive Distribution Rights

Our general partner or its affiliates or a subsequent holder may transfer its incentive distribution rights to an affiliate of the holder (other than an individual) or another entity as part of the merger or consolidation of such holder with or into another entity, the sale of all of the ownership interest in the holder or the sale of all or substantially all of its assets to that entity without the prior approval of the unitholders. Prior to December 31, 2017, other transfers of incentive distribution rights will require the affirmative vote of holders of a majority of the outstanding common units, excluding common units held by our general partner and its affiliates. On or after December 31, 2017, the incentive distribution rights will be freely transferable.

Change of Management Provisions

Our partnership agreement contains specific provisions that are intended to discourage a person or group from attempting to remove El Paso Pipeline GP Company, L.L.C. as our general partner or otherwise change our management. If any person or group other than our general partner and its affiliates acquires beneficial ownership of 20 percent or more of any class of units, that person or group loses voting rights on all of its units. This loss of voting rights does not apply to any person or group that acquires the units from our general partner or its affiliates and any transferees of that person or group approved by our general partner or to any person or group who acquires the units with the prior approval of the board of directors of our general partner.

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Our partnership agreement also provides that if our general partner is removed as our general partner under circumstances where cause does not exist and units held by our general partner and its affiliates are not voted in favor of that removal:

•: any existing arrearages in payment of the minimum quarterly distribution on the common units will be extinguished; and
•: our general partner will have the right to convert its general partner units and its incentive distribution rights into common units or to receive cash in exchange for those interests based on the fair market value of those interests at that time.

Limited Call Right

If at any time our general partner and its affiliates own more than 75 percent of the then-issued and outstanding limited partner interests of any class, our general partner will have the right, which it may assign in whole or in part to any of its affiliates or to us, to acquire all, but not less than all, of the limited partner interests of the class held by unaffiliated persons as of a record date to be selected by our general partner, on at least 10 but not more than 60 days notice. The purchase price in the event of this purchase is the greater of:

•: the highest cash price paid by either of our general partner or any of its affiliates for any limited partner interests of the class purchased within the 90 days preceding the date on which our general partner first mails notice of its election to purchase those limited partner interests; and
•: the current market price as of the date three days before the date the notice is mailed.

As a result of our general partner's right to purchase outstanding limited partner interests, a holder of limited partner interests may have his limited partner interests purchased at a price that may be lower than market prices at various times prior to such purchase or lower than a unitholder may anticipate the market price to be in the future. The tax consequences to a unitholder of the exercise of this call right are the same as a sale by that unitholder of his common units in the market. Please read "Material Tax Considerations—Disposition of Common Units."

Non-Taxpaying Assignees; Redemption

To avoid any adverse effect on the maximum applicable rates chargeable to customers by our subsidiaries that are regulated interstate natural gas pipelines, or in order to reverse an adverse determination that has occurred regarding such maximum rate, transferees are required to fill out a properly completed transfer application certifying, and our general partner, acting on our behalf, may at any time require each unitholder to re-certify:

•: that the transferee or unitholder is an individual or an entity subject to U.S. federal income taxation on the income generated by us; or
•: that, if the transferee unitholder is an entity not subject to U.S. federal income taxation on the income generated by us, as in the case, for example, of a mutual fund taxed as a regulated investment company or a partnership, all the entity's owners are subject to U.S. federal income taxation on the income generated by us.

This certification can be changed in any manner our general partner determines is necessary or appropriate to implement its original purpose.

If a unitholder fails to furnish:

•: a transfer application containing the required certification;
•: a re-certification containing the required certification within 30 days after request; or

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•: provides a false certification; then

we will have the right, which we may assign to any of our affiliates, to acquire all but not less than all of the units held by such unitholder. Further, the units will not be entitled to any allocations of income or loss, distributions or voting rights while held by such unitholder.

The purchase price in the event of such an acquisition for each unit held by such unitholder will be the lesser of:

(1) the price paid by such unitholder for the relevant unit; and

(2) the current market price as of the date three days before the date the notice is mailed.

The purchase price will be paid in cash or by delivery of a promissory note, as determined by our general partner. Any such promissory note will bear interest at the rate of five percent annually and be payable in three equal annual installments of principal and accrued interest, commencing one year after the redemption date.

Meetings; Voting

Except as described below regarding a person or group owning 20 percent or more of any class of units then outstanding, record holders of units on the record date are entitled to notice of, and to vote at, meetings of our limited partners and to act upon matters for which approvals may be solicited.

Any action that is required or permitted to be taken by the unitholders may be taken either at a meeting of the unitholders or without a meeting if consents in writing describing the action so taken are signed by holders of the number of units necessary to authorize or take that action at a meeting. Meetings of the unitholders may be called by our general partner or by unitholders owning at least 20 percent of the outstanding units of the class for which a meeting is proposed. Unitholders may vote either in person or by proxy at meetings. The holders of a majority of the outstanding units of the class or classes for which a meeting has been called represented in person or by proxy will constitute a quorum unless any action by the unitholders requires approval by holders of a greater percentage of the units, in which case the quorum will be the greater percentage.

Each record holder of a unit has a vote according to his percentage interest in us, although additional limited partner interests having special voting rights could be issued. Please read "—Issuance of Additional Securities." However, if at any time any person or group, other than our general partner and its affiliates, or a direct or subsequently approved transferee of our general partner or its affiliates, acquires, in the aggregate, beneficial ownership of 20 percent or more of any class of units then outstanding, that person or group will lose voting rights on all of its units and the units may not be voted on any matter and will not be considered to be outstanding when sending notices of a meeting of unitholders, calculating required votes, determining the presence of a quorum or for other similar purposes. Common units held in nominee or street name account will be voted by the broker or other nominee in accordance with the instruction of the beneficial owner unless the arrangement between the beneficial owner and his nominee provides otherwise.

Any notice, demand, request, report or proxy material required or permitted to be given or made to record holders of common units under our partnership agreement will be delivered to the record holder by us or by the transfer agent.

Status as Limited Partner

By transfer of common units in accordance with our partnership agreement, each transferee of common units shall be admitted as a limited partner with respect to the common units transferred when such transfer and admission is reflected in our books and records. Except as described under

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"—Limited Liability," the common units will be fully paid, and unitholders will not be required to make additional contributions.

Non-Citizen Assignees; Redemption

If we are or become subject to federal, state or local laws or regulations that, in the reasonable determination of our general partner, create a substantial risk of cancellation or forfeiture of any property that we have an interest in because of the nationality, citizenship or other related status of any limited partner, we may redeem the units held by the limited partner at their current market price. In order to avoid any cancellation or forfeiture, our general partner may require each limited partner to furnish information about his nationality, citizenship or related status. If a limited partner fails to furnish information about his nationality, citizenship or other related status within 30 days after a request for the information or our general partner determines after receipt of the information that the limited partner is not an eligible citizen, the limited partner may be treated as a non-citizen assignee. A non-citizen assignee is entitled to an interest equivalent to that of a limited partner for the right to share in allocations and distributions from us, including liquidating distributions. A non-citizen assignee does not have the right to direct the voting of his units and may not receive distributions in-kind upon our liquidation.

Indemnification

Under our partnership agreement, in most circumstances, we will indemnify the following persons, to the fullest extent permitted by law, from and against all losses, claims, damages or similar events:

•: our general partner;
•: any departing general partner;
•: any person who is or was an affiliate of a general partner or any departing general partner;
•: any person who is or was a director, officer, member, partner, fiduciary or trustee of any entity set forth in the preceding three bullet points;
•: any person who is or was serving as director, officer, member, partner, fiduciary or trustee of another person at the request of our general partner or any departing general partner; and
•: any person designated by our general partner.

Any indemnification under these provisions will only be out of our assets. Unless it otherwise agrees, our general partner will not be personally liable for, or have any obligation to contribute or lend funds or assets to us to enable us to effectuate, indemnification. We may purchase insurance against liabilities asserted against and expenses incurred by persons for our activities, regardless of whether we would have the power to indemnify the person against liabilities under our partnership agreement.

Reimbursement of Expenses

Our partnership agreement requires us to reimburse our general partner for all direct and indirect expenses it incurs or payments it makes on our behalf and all other expenses allocable to us or otherwise incurred by our general partner in connection with operating our business. These expenses include salary, benefits, bonus, incentive compensation and other amounts paid to persons who perform services for us or on our behalf and expenses allocated to our general partner by its affiliates. The general partner is entitled to determine in good faith the expenses that are allocable to us. Please read "Certain Relationships and Related Transactions and Director Independence—Omnibus Agreement" and "Certain Relationships and Related Transactions and Director Independence—Reimbursement of

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Operating and General and Administrative Expense," both in our Annual Report on Form 10-K for the year ended December 31, 2012.

Books and Reports

Our general partner is required to keep appropriate books of our business at our principal offices. The books are maintained for both tax and financial reporting purposes on an accrual basis. For tax and fiscal reporting purposes, our fiscal year is the calendar year.

We will furnish or make available to record holders of common units, within 120 days after the close of each fiscal year, an annual report containing audited financial statements and a report on those financial statements by our independent public accountants. Except for our fourth quarter, we will also furnish or make available summary financial information within 90 days after the close of each quarter.

We will furnish each record holder of a unit with information reasonably required for tax reporting purposes within 90 days after the close of each calendar year. This information is expected to be furnished in summary form so that some complex calculations normally required of partners can be avoided. Our ability to furnish this summary information to unitholders will depend on the cooperation of unitholders in supplying us with specific information. Every unitholder will receive information to assist him in determining his federal and state tax liability and filing his federal and state income tax returns, regardless of whether he supplies us with information.

Right to Inspect Our Books and Records

Our partnership agreement provides that a limited partner can, for a purpose reasonably related to his interest as a limited partner, upon reasonable written demand stating the purpose of such demand and at his own expense, have furnished to him:

•: a current list of the name and last known address of each partner;
•: a copy of our tax returns;
•: information as to the amount of cash, and a description and statement of the agreed value of any other property or services, contributed or to be contributed by each partner and the date on which each partner became a partner;
•: copies of our partnership agreement, our certificate of limited partnership, related amendments and powers of attorney under which they have been executed;
•: information regarding the status of our business and financial condition; and
•: any other information regarding our affairs as is just and reasonable.

Our general partner may, and intends to, keep confidential from the limited partners, trade secrets or other information the disclosure of which our general partner believes in good faith is not in our best interests or that we are required by law or by agreements with third parties to keep confidential.

Registration Rights

Under our partnership agreement, we have agreed to register for resale under the Securities Act and applicable state securities laws any common units or other partnership securities proposed to be sold by our general partner or any of its affiliates or their assignees if an exemption from the registration requirements is not otherwise available. These registration rights continue for two years following any withdrawal or removal of El Paso Pipeline GP Company, L.L.C. as general partner.

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MODIFICATION OF FIDUCIARY DUTIES OWED TO THE LIMITED PARTNERS

Our general partner is accountable to us and our unitholders as a fiduciary. Fiduciary duties owed to unitholders by our general partner are prescribed by law and the partnership agreement. The Delaware Act provides that Delaware limited partnerships may, in their partnership agreements, expand, restrict or eliminate the fiduciary duties otherwise owed by a general partner to limited partners and the partnership.

Our partnership agreement contains various provisions modifying and restricting the fiduciary duties that might otherwise be owed by our general partner. We have adopted these provisions to allow our general partner or its affiliates to engage in transactions with us that otherwise might be prohibited by state-law fiduciary standards and to take into account the interests of other parties in addition to our interests when resolving conflicts of interest. We believe this is appropriate and necessary because the board of directors of our general partner has fiduciary duties to manage our general partner in a manner beneficial both to its owner, KMI, as well as to our unitholders. Without these modifications, the general partner's ability to make decisions involving conflicts of interests would be restricted. The modifications to the fiduciary standards benefit our general partner by enabling it to take into consideration all parties involved in the proposed action. These modifications also strengthen the ability of our general partner to attract and retain experienced and capable directors. These modifications represent a detriment to the common unitholders because they restrict the remedies available to unitholders for actions that, without those limitations, might constitute breaches of fiduciary duty, as described below, and permit our general partner to take into account the interests of third parties in addition to our interests when resolving conflicted interests. The following is a summary of:

•: the fiduciary duties imposed on our general partner by the Delaware Act;
•: material modifications of these duties contained in our partnership agreement; and
•: certain rights and remedies of unitholders contained in the Delaware Act.


State law fiduciary duty standards		Fiduciary duties are generally considered to include an obligation to act in good faith and with due care and loyalty. The duty of care, in the absence of a provision in a partnership agreement providing otherwise, would generally require a general partner to act for the partnership in the same manner as a prudent person would act on his own behalf. The duty of loyalty, in the absence of a provision in a partnership agreement providing otherwise, would generally prohibit a general partner of a Delaware limited partnership from taking any action or engaging in any transaction where a conflict of interest is present.
Partnership agreement modified standards		Our partnership agreement contains provisions that waive or consent to conduct by our general partner and its affiliates that might otherwise raise issues as to compliance with fiduciary duties or applicable law. For example, Section 7.9 of our partnership agreement provides that when our general partner is acting in its capacity as our general partner, as opposed to in its individual capacity, it must act in "good faith" and will not be subject to any other standard under applicable law. In addition, when our general partner is acting in its individual capacity, as opposed to in its capacity as our general partner, it may act without any fiduciary obligation to us or the unitholders whatsoever. These standards reduce the obligations to which our general partner would otherwise be held under applicable Delaware law.

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		Our partnership agreement generally provides that affiliated transactions and resolutions of conflicts of interest not involving a vote of unitholders and that are not approved by the conflicts committee of the board of directors of our general partner must be:
		• on terms no less favorable to us than those generally being provided to or available from unrelated third parties; or
		• "fair and reasonable" to us, which may take into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous, or unfavorable or disadvantageous, to us).
		If our general partner does not seek approval from the conflicts committee and the board of directors of our general partner determines that the resolution or course of action taken with respect to the conflict of interest satisfies either of the standards set forth in the bullet points above, then it will be presumed that, in making its decision, the board of directors, which may include board members affected by the conflict of interest, acted in good faith, and in any proceeding brought by or on behalf of any limited partner or the partnership, the person bringing or prosecuting such proceeding will have the burden of overcoming such presumption. These standards reduce the obligations to which our general partner would otherwise be held. In addition to the other more specific provisions limiting the obligations of our general partner, our partnership agreement further provides that our general partner, its affiliates and their officers and directors will not be liable for monetary damages to us or our limited partners for errors of judgment or for any acts or omissions unless there has been a final and non-appealable judgment by a court of competent jurisdiction determining that our general partner or its officers and directors acted in bad faith or engaged in fraud or willful misconduct.
Rights and remedies of unitholders		The Delaware Act generally provides that a limited partner may institute legal action on behalf of the partnership to recover damages from a third party where a general partner has refused to institute the action or where an effort to cause a general partner to do so is not likely to succeed. These actions include actions against a general partner for breach of its fiduciary duties or of the partnership agreement. In addition, the statutory or case law of some jurisdictions may permit a limited partner to institute legal action on behalf of himself and all other similarly situated limited partners to recover damages from a general partner for violations of its fiduciary duties to the limited partners.

In order to become one of our limited partners, a common unitholder is required to agree to be bound by the provisions in the partnership agreement, including the provisions discussed above. This is in accordance with the policy of the Delaware Act favoring the principle of freedom of contract and the enforceability of partnership agreements. The failure of a limited partner to sign our partnership agreement does not render the partnership agreement unenforceable against that person.

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Under the partnership agreement, we must indemnify our general partner and its officers, directors and managers, to the fullest extent permitted by law, against liabilities, costs and expenses incurred by our general partner or these other persons. We must provide this indemnification unless there has been a final and non-appealable judgment by a court of competent jurisdiction determining that these persons acted in bad faith or engaged in fraud or willful misconduct. We also must provide this indemnification for criminal proceedings unless our general partner or these other persons acted with knowledge that their conduct was unlawful. Thus, our general partner could be indemnified for its negligent acts if it meets the requirements set forth above. To the extent that these provisions purport to include indemnification for liabilities arising under the Securities Act, in the opinion of the SEC such indemnification is contrary to public policy and therefore unenforceable.

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MATERIAL TAX CONSEQUENCES

This section is a discussion of the material tax considerations that may be relevant to prospective unitholders who are individual citizens or residents of the U.S. and, unless otherwise noted in the following discussion, is the opinion of Andrews Kurth LLP, counsel to our general partner and us, insofar as it relates to matters of U.S. federal income tax law and legal conclusions with respect to those matters. This section is based upon current provisions of the Internal Revenue Code of 1986, as amended, or the Internal Revenue Code, existing and proposed regulations and current administrative rulings and court decisions, all of which are subject to change. Later changes in these authorities may cause the tax consequences to vary substantially from the consequences described below. Unless the context otherwise requires, references in this section to "us" or "we" are references to El Paso Pipeline Partners, L.P. and El Paso Pipeline Partners Operating Company, L.L.C., our operating company.

The following discussion does not address all federal income tax matters affecting us or the unitholders. Moreover, the discussion focuses on unitholders who are individual citizens or residents of the U.S. and has only limited application to corporations, estates, trusts, nonresident aliens or other unitholders subject to specialized tax treatment, such as tax-exempt institutions, foreign persons, individual retirement accounts (IRAs), real estate investment trusts (REITs), employee benefit plans or mutual funds. Accordingly, we urge each prospective unitholder to consult, and depend on, his own tax advisor in analyzing the federal, state, local and foreign tax consequences particular to him of the ownership or disposition of the common units.

All statements as to matters of law and legal conclusions, but not as to factual matters, contained in this section, unless otherwise noted, are the opinion of Andrews Kurth LLP and are based on the accuracy of the representations made by us and our general partner.

No ruling has been or will be requested from the IRS regarding any matter affecting us or prospective unitholders. Instead, we will rely on opinions and advice of Andrews Kurth LLP. Unlike a ruling, an opinion of counsel represents only that counsel's best legal judgment and does not bind the IRS or the courts. Accordingly, the opinions and statements made in this discussion may not be sustained by a court if contested by the IRS. Any contest of this sort with the IRS may materially and adversely impact the market for the common units and the prices at which the common units trade. In addition, the costs of any contest with the IRS, principally legal, accounting and related fees, will result in a reduction in cash available to pay distributions to our unitholders and our general partner and thus will be borne indirectly by our unitholders and our general partner. Furthermore, the tax treatment of us, or of an investment in us, may be significantly modified by future legislative or administrative changes or court decisions. Any modifications may or may not be retroactively applied.

For the reasons described below, Andrews Kurth LLP has not rendered an opinion with respect to the following specific federal income tax issues:

•: the treatment of a unitholder whose common units are loaned to a short seller to cover a short sale of common units (please read "—Tax Consequences of Unit Ownership—Treatment of Short Sales");
•: whether our monthly convention for allocating taxable income and losses is permitted by existing Treasury Regulations (please read "—Disposition of Common Units—Allocations Between Transferors and Transferees"); and
•: whether our method for depreciating Section 743 adjustments is sustainable in certain cases (please read "—Tax Consequences of Unit Ownership—Section 754 Election" and "—Uniformity of Units").

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Partnership Status

A partnership is not a taxable entity and incurs no federal income tax liability. Instead, each partner of a partnership is required to take into account his share of items of income, gain, loss and deduction of the partnership in computing his federal income tax liability, regardless of whether cash distributions are made to him by the partnership. Distributions by a partnership to a partner are generally not taxable to the partner unless the amount of cash distributed is in excess of the partner's adjusted basis in his partnership interest.

Section 7704 of the Internal Revenue Code provides that publicly traded partnerships will, as a general rule, be taxed as corporations. However, an exception, referred to as the "Qualifying Income Exception," exists with respect to publicly traded partnerships of which 90 percent or more of the gross income for every taxable year consists of "qualifying income." Qualifying income includes income and gains derived from the transportation, storage and processing of crude oil, natural gas and products thereof. Other types of qualifying income include interest (other than from a financial business), dividends, gains from the sale of real property and gains from the sale or other disposition of capital assets held for the production of income that otherwise constitutes qualifying income. We estimate that less than 5 percent of our current gross income is not qualifying income; however, this estimate could change from time to time. Based on and subject to this estimate, the factual representations made by us and our general partner and a review of the applicable legal authorities, Andrews Kurth LLP is of the opinion that at least 90 percent of our current gross income constitutes qualifying income. The portion of our income that is qualifying income can change from time to time.

No ruling has been or will be sought from the IRS and the IRS has made no determination as to our status for federal income tax purposes or whether our operations generate "qualifying income" under Section 7704 of the Internal Revenue Code. Instead, we will rely on the opinion of Andrews Kurth LLP on such matters. It is the opinion of Andrews Kurth LLP that, based upon the Internal Revenue Code, its regulations, published revenue rulings and court decisions and the representations described below, we will be classified as a partnership and the operating company will be disregarded as an entity separate from us for federal income tax purposes.

In rendering its opinion, Andrews Kurth LLP has relied on factual representations made by us and our general partner. The representations made by us and our general partner upon which Andrews Kurth LLP has relied include:

(a) Neither we nor our operating company have elected nor will elect to be treated as a corporation; and

(b) For each taxable year, more than 90 percent of our gross income has been and will be income that Andrews Kurth LLP has opined or will opine is "qualifying income" within the meaning of Section 7704(d) of the Internal Revenue Code.

If we fail to meet the Qualifying Income Exception, other than a failure that is determined by the IRS to be inadvertent and that is cured within a reasonable time after discovery (in which case the IRS may also require us to make adjustments with respect to our unitholders or pay other amounts), we will be treated as if we had transferred all of our assets, subject to liabilities, to a newly formed corporation, on the first day of the year in which we fail to meet the Qualifying Income Exception, in return for stock in that corporation, and then distributed that stock to the unitholders in liquidation of their interests in us. This deemed contribution and liquidation should be tax-free to unitholders and us except to the extent that our liabilities exceed the tax bases of our assets at that time. Thereafter, we would be treated as a corporation for federal income tax purposes.

If we were taxable as a corporation in any taxable year, either as a result of a failure to meet the Qualifying Income Exception or otherwise, our items of income, gain, loss and deduction would be reflected only on our tax return rather than being passed through to the unitholders, and our net

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income would be taxed to us at corporate rates. In addition, any distribution made to a unitholder would be treated as either taxable dividend income, to the extent of our current or accumulated earnings and profits, or, in the absence of earnings and profits, a nontaxable return of capital, to the extent of the unitholder's tax basis in his common units, or taxable capital gain, after the unitholder's tax basis in his common units is reduced to zero. Accordingly, taxation as a corporation would result in a material reduction in a unitholder's cash flow and after-tax return and thus would likely result in a substantial reduction of the value of the units.

The discussion below is based on Andrews Kurth LLP's opinion that we will be classified as a partnership for federal income tax purposes.

Limited Partner Status

Unitholders who have become limited partners of El Paso Pipeline Partners, L.P. will be treated as partners of El Paso Pipeline Partners, L.P. for federal income tax purposes. Also, unitholders whose common units are held in street name or by a nominee and who have the right to direct the nominee in the exercise of all substantive rights attendant to the ownership of their common units will be treated as partners of El Paso Pipeline Partners, L.P. for federal income tax purposes.

A beneficial owner of common units whose units have been transferred to a short seller to complete a short sale would appear to lose his status as a partner with respect to those units for federal income tax purposes. Please read "—Tax Consequences of Unit Ownership—Treatment of Short Sales."

Items of our income, gain, loss or deduction are not reportable by a unitholder who is not a partner for federal income tax purposes, and any cash distributions received by a unitholder who is not a partner for federal income tax purposes would therefore be fully taxable as ordinary income. These holders are urged to consult their own tax advisors with respect to their status as partners in El Paso Pipeline Partners, L.P. for federal income tax purposes. The references to "unitholders" in the discussion that follows are to persons who are treated as partners in El Paso Pipeline Partners, L.P. for federal income tax purposes.

Tax Consequences of Unit Ownership

Flow-Through of Taxable Income. We do not pay any federal income tax. Instead, each unitholder is required to report on his income tax return his share of our income, gains, losses and deductions without regard to whether corresponding cash distributions are received by him. Consequently, we may allocate income to a unitholder even if he has not received a cash distribution. Each unitholder will be required to include in income his allocable share of our income, gains, losses and deductions for our taxable year or years ending with or within his taxable year. Our taxable year ends on December 31.

Treatment of Distributions. Distributions by us to a unitholder generally will not be taxable to the unitholder for federal income tax purposes, except to the extent the amount of any such cash distribution exceeds his tax basis in his common units immediately before the distribution. Our cash distributions in excess of a unitholder's tax basis in his common units generally will be considered to be gain from the sale or exchange of the common units, taxable in accordance with the rules described under "—Disposition of Common Units" below. Any reduction in a unitholder's share of our liabilities for which no partner, including our general partner, bears the economic risk of loss, known as "non-recourse liabilities," will be treated as a distribution of cash to that unitholder. To the extent our distributions cause a unitholder's "at risk" amount to be less than zero at the end of any taxable year, the unitholder must recapture any losses deducted in previous years. Please read "—Limitations on Deductibility of Losses."

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A decrease in a unitholder's percentage interest in us because of our issuance of additional common units will decrease his share of our non-recourse liabilities, and thus will result in a corresponding deemed distribution of cash, which may constitute a non-pro rata distribution. A non-pro rata distribution of money or property may result in ordinary income to a unitholder, regardless of his tax basis in his common units, if the distribution reduces the unitholder's share of our "unrealized receivables," including depreciation recapture, and/or substantially appreciated "inventory items," both as defined in Section 751 of the Internal Revenue Code, and collectively, "Section 751 Assets." To that extent, he will be treated as having been distributed his proportionate share of the Section 751 Assets and having then exchanged those assets with us in return for the non-pro rata portion of the actual distribution made to him. This latter deemed exchange will generally result in the unitholder's realization of ordinary income, which will equal the excess of the non-pro rata portion of that distribution over the unitholder's tax basis for the share of Section 751 Assets deemed relinquished in the exchange.

Basis of Common Units. A unitholder's initial tax basis for his common units will be the amount he paid for the common units plus his share of our non-recourse liabilities. That basis will be increased by his share of our income and by any increases in his share of our non-recourse liabilities. That basis generally will be decreased, but not below zero, by distributions from us, by the unitholder's share of our losses, by any decreases in his share of our non-recourse liabilities and by his share of our expenditures that are not deductible in computing taxable income and are not required to be capitalized. A unitholder will have no share of our debt that is recourse to our general partner or its affiliates, but will have a share, generally based on his share of profits, of our non-recourse liabilities. Please read "—Disposition of Common Units—Recognition of Gain or Loss."

Limitations on Deductibility of Losses. The deduction by a unitholder of his share of our losses will be limited to the tax basis in his units and, in the case of an individual unitholder or a corporate unitholder, if more than 50 percent of the value of the corporate unitholder's stock is owned directly or indirectly by or for five or fewer individuals or some tax-exempt organizations, to the amount for which the unitholder is considered to be "at risk" with respect to our activities, if that amount is less than his tax basis. A unitholder subject to these limitations must recapture losses deducted in previous years to the extent that distributions cause his at risk amount to be less than zero at the end of any taxable year. Losses disallowed to a unitholder or recaptured as a result of these limitations will carry forward and will be allowable as a deduction in a later year to the extent that his tax basis or at risk amount, whichever is the limiting factor, is subsequently increased provided that such losses are otherwise allowable. Upon the taxable disposition of a unit, any gain recognized by a unitholder can be offset by losses that were previously suspended by the at risk limitation but may not be offset by losses suspended by the basis limitation. Any excess loss above that gain previously suspended by the at risk or basis limitations is no longer utilizable.

In general, a unitholder will be at risk to the extent of the tax basis of his units, excluding any portion of that basis attributable to his share of our non-recourse liabilities, reduced by (i) any portion of that basis representing amounts other than were protected against loss because of a guarantee, stop-loss agreement or other similar arrangement and (ii) any amount of money he borrows to acquire or hold his units, if the lender of those borrowed funds owns an interest in us, is related to the unitholder or can look only to the units for repayment. A unitholder's at risk amount will increase or decrease as the tax basis of the unitholder's units increases or decreases, other than tax basis increases or decreases attributable to increases or decreases in his share of our non-recourse liabilities.

In addition to the basis and at-risk limitations on the deductibility of losses, the passive loss limitations generally provide that individuals, estates, trusts and some closely-held corporations and personal service corporations are permitted to deduct losses from passive activities, which are generally trade or business activities in which the taxpayer does not materially participate, only to the extent of the taxpayer's income from those passive activities. The passive loss limitations are applied separately

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with respect to each publicly traded partnership. Consequently, any passive losses we generate will only be available to offset our passive income generated in the future and will not be available to offset income from other passive activities or investments, including our investments or investments in other publicly traded partnerships, or a unitholder's salary or active business income. Passive losses that are not deductible because they exceed a unitholder's share of income we generate may be deducted in full when the unitholder disposes of his entire investment in us in a fully taxable transaction with an unrelated party. The passive activity loss limitations are applied after other applicable limitations on deductions, including the at risk rules and the basis limitation.

A unitholder's share of our net income may be offset by any of our suspended passive losses, but it may not be offset by any other current or carryover losses from other passive activities, including those attributable to other publicly traded partnerships.

Limitations on Interest Deductions. The deductibility of a non-corporate taxpayer's "investment interest expense" is generally limited to the amount of that taxpayer's "net investment income." Investment interest expense includes:

•: interest on indebtedness properly allocable to property held for investment;
•: our interest expense attributed to portfolio income; and
•: the portion of interest expense incurred to purchase or carry an interest in a passive activity to the extent attributable to portfolio income.

The computation of a unitholder's investment interest expense will take into account interest on any margin account borrowing or other loan incurred to purchase or carry a unit. Net investment income includes gross income from property held for investment and amounts treated as portfolio income under the passive loss rules, less deductible expenses, other than interest, directly connected with the production of investment income, but generally does not include gains attributable to the disposition of property held for investment. The IRS has indicated that net passive income earned by a publicly traded partnership will be treated as investment income to its unitholders for purposes of the investment interest deduction limitation. In addition, the unitholder's share of our portfolio income will be treated as investment income.

Entity-Level Collections. If we are required or elect under applicable law to pay any federal, state, local or foreign income tax on behalf of any unitholder or our general partner or any former unitholder, we are authorized to pay those taxes from our funds. That payment, if made, will be treated as a distribution of cash to the unitholder on whose behalf the payment was made. If the payment is made on behalf of a person whose identity cannot be determined, we are authorized to treat the payment as a distribution to all current unitholders. We are authorized to amend the partnership agreement in the manner necessary to maintain uniformity of intrinsic tax characteristics of units and to adjust later distributions, so that after giving effect to these distributions, the priority and characterization of distributions otherwise applicable under the partnership agreement is maintained as nearly as is practicable. Payments by us as described above could give rise to an overpayment of tax on behalf of an individual unitholder in which event the unitholder would be required to file a claim in order to obtain a credit or refund.

Allocation of Income, Gain, Loss and Deduction. In general, if we have a net profit, our items of income, gain, loss and deduction will be allocated among our general partner and the unitholders in accordance with their percentage interests in us. At any time that incentive distributions are made to our general partner, gross income will be allocated to the general partner to the extent of these distributions. If we have a net loss for the entire year, that loss will be allocated first to our general partner and the unitholders in accordance with their percentage interests in us to the extent of their positive capital accounts and, second, to our general partner.

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Specified items of our income, gain, loss and deduction will be allocated under Section 704(c) of the Internal Revenue Code to account for the difference between the tax basis and fair market value of our assets at the time of an offering, referred to in this discussion as "Contributed Property." These allocations are required to eliminate the difference between a partner's "book" capital account, credited with the fair market value of Contributed Property, and the "tax" capital account, credited with the tax basis of Contributed Property, referred to in this discussion as the "Book-Tax Disparity." The effect of these allocations to a unitholder purchasing common units from us in an offering will be essentially the same as if the tax basis of Contributed Property was equal to its fair market value at the time of such offering. In the event we issue additional common units or engage in certain other transactions in the future, "reverse Section 704(c) allocations," similar to the Section 704(c) allocations described above, will be made to all persons who are holders of partnership interests immediately prior to such other transaction to account for the difference between the "book" basis for purposes of maintaining capital accounts and the fair market value of all property held by us at the time of the future transaction. In addition, items of recapture income will be allocated to the extent possible to the unitholder who was allocated the deduction giving rise to the treatment of that gain as recapture income in order to minimize the recognition of ordinary income by other unitholders. Finally, although we do not expect that our operations will result in the creation of negative capital accounts, if negative capital accounts nevertheless result, items of our income and gain will be allocated in an amount and manner sufficient to eliminate the negative balance as quickly as possible.

An allocation of items of our income, gain, loss or deduction, other than an allocation required by Section 704(c) to eliminate the Book-Tax Disparity, will generally be given effect for federal income tax purposes in determining a partner's share of an item of income, gain, loss or deduction only if the allocation has substantial economic effect. In any other case, a partner's share of an item will be determined on the basis of his interest in us, which will be determined by taking into account all the facts and circumstances, including:

•: his relative contributions to us;
•: the interests of all the partners in profits and losses;
•: the interest of all the partners in cash flow; and
•: the rights of all the partners to distributions of capital upon liquidation.

Andrews Kurth LLP is of the opinion that, with the exception of the issues described in "—Tax Consequences of Unit Ownership—Section 754 Election," "—Uniformity of Units" and "—Disposition of Common Units—Allocations Between Transferors and Transferees," allocations under our partnership agreement will be given effect for federal income tax purposes in determining a partner's share of an item of income, gain, loss or deduction.

Treatment of Short Sales. A unitholder whose units are loaned to a "short seller" to cover a short sale of units may be considered as having disposed of those units. If so, he would no longer be a partner for tax purposes with respect to those units during the period of the loan and may recognize gain or loss from the disposition. As a result, during this period:

•: any of our income, gain, loss or deduction with respect to those units would not be reportable by the unitholder;
•: any cash distributions received by the unitholder as to those units would be fully taxable; and
•: all of these distributions would appear to be ordinary income.

Andrews Kurth LLP has not rendered an opinion regarding the treatment of a unitholder where common units are loaned to a short seller to cover 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

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seller are urged to modify any applicable brokerage account agreements to prohibit their brokers from borrowing and loaning their units. The IRS has announced that it is studying issues relating to the tax treatment of short sales of partnership interests. Please also read "—Disposition of Common Units—Recognition of Gain or Loss."

Alternative Minimum Tax. Each unitholder will be required to take into account his distributive share of any items of our income, gain, loss or deduction for purposes of the alternative minimum tax. The current minimum tax rate for non-corporate taxpayers is 26 percent on the first $179,500 of alternative minimum taxable income in excess of the exemption amount and 28 percent on any additional alternative minimum taxable income. Prospective unitholders are urged to consult with their tax advisors as to the impact of an investment in units on their liability for the alternative minimum tax.

Tax Rates. Under current law, the highest marginal United States federal income tax rate applicable to ordinary income of individuals is 39.6% and the maximum United States federal income tax rate for net capital gains of an individual is 20% if the asset disposed of was a capital asset held for more than 12 months at the time of disposition. These rates are subject to change by new legislation at any time.

A 3.8 percent Medicare tax on certain net investment income earned by individuals, estates, and trusts applies for taxable years beginning after December 31, 2012. For these purposes, net investment income generally includes a unitholder's allocable share of our income and gain realized by a unitholder from a sale of units. In the case of an individual, the tax will be imposed on the lesser of (i) the unitholder's net investment income from all investments, or (ii) the amount by which the unitholder's modified adjusted gross income exceeds $250,000 (if the unitholder is married and filing jointly or a surviving spouse), $125,000 (if the unitholder is married and filing separately) or $200,000 (in any other case). In the case of an estate or trust, the tax will be imposed on the lesser of (i) undistributed net investment income, or (ii) the excess adjusted gross income over the dollar amount at which the highest income tax bracket applicable to an estate or trust begins.

Section 754 Election. We have made the election permitted by Section 754 of the Internal Revenue Code. That election is irrevocable without the consent of the IRS. The election generally permits us to adjust a common unit purchaser's tax basis in our assets ("inside basis") under Section 743(b) of the Internal Revenue Code to reflect his purchase price. This election applies to a person who purchases units from a selling unitholder but does not apply to a person who purchases common units directly from us. The Section 743(b) adjustment belongs to the purchaser and not to other unitholders. For purposes of this discussion, a unitholder's inside basis in our assets will be considered to have two components: (1) his share of our tax basis in our assets ("common basis") and (2) his Section 743(b) adjustment to that basis.

Treasury Regulations under Section 743 of the Internal Revenue Code require, if the remedial allocation method is adopted (which we have adopted), a portion of the Section 743(b) adjustment that is attributable to recovery property subject to depreciation under Section 168 of the Internal Revenue Code to be depreciated over the remaining cost recovery period for the property's unamortized Book-Tax Disparity. Under Treasury Regulation Section 1.167(c)-1(a)(6), a Section 743(b) adjustment attributable to property subject to depreciation under Section 167 of the Internal Revenue Code, rather than cost recovery deductions under Section 168, is generally required to be depreciated using either the straight-line method or the 150% declining balance method. Under our partnership agreement, our general partner is authorized to take a position to preserve the uniformity of units even if that position is not consistent with these and any other Treasury Regulations. Please read "—Uniformity of Units."

Although Andrews Kurth LLP is unable to opine as to the validity of this approach because there is no controlling authority on this issue, we intend to depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of Contributed Property, to the extent

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of any unamortized Book-Tax Disparity, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the unamortized Book-Tax Disparity of the property, or treat that portion as non-amortizable to the extent attributable to property which is not amortizable. This method is consistent with methods employed by other publicly traded partnerships but is arguably inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6), which is not expected to directly apply to a material portion of our assets. To the extent this Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Book-Tax Disparity, we will apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may take a depreciation or amortization position under which all purchasers acquiring units in the same month would receive depreciation or amortization, whether attributable to common basis or a Section 743(b) adjustment, based upon the same applicable rate as if they had purchased a direct interest in our assets. This kind of aggregate approach may result in lower annual depreciation or amortization deductions than would otherwise be allowable to some unitholders. Please read "—Uniformity of Units." A unitholder's tax basis for his common units is reduced by his share of our deductions (whether or not such deductions were claimed on an individual's income tax return) so that any position we take that understates deductions will overstate the common unitholder's basis in his common units, which may cause the unitholder to understate gain or overstate loss on any sale of such units. Please read "—Disposition of Common Units—Recognition of Gain or Loss." The IRS may challenge our position with respect to depreciating or amortizing the Section 743(b) adjustment we take to preserve the uniformity of the units. If such a challenge were sustained, the gain from the sale of units might be increased without the benefit of additional deductions.

A Section 754 election is advantageous if the transferee's tax basis in his units is higher than the units' share of the aggregate tax basis of our assets immediately prior to the transfer. In that case, as a result of the election, the transferee would have, among other items, a greater amount of depreciation deductions and his share of any gain or loss on a sale of our assets would be less. Conversely, a Section 754 election is disadvantageous if the transferee's tax basis in his units is lower than those units' share of the aggregate tax basis of our assets immediately prior to the transfer. Thus, the fair market value of the units may be affected either favorably or unfavorably by the election. A basis adjustment is required regardless of whether a Section 754 election is made in the case of a transfer of an interest in us if we have a substantial built-in loss immediately after the transfer, or if we distribute property and have a substantial basis reduction. Generally a basis reduction or a built-in loss is substantial if it exceeds $250,000.

The calculations involved in the Section 754 election are complex and will be made on the basis of assumptions as to the value of our assets and other matters. For example, the allocation of the Section 743(b) adjustment among our assets must be made in accordance with the Internal Revenue Code. The IRS could seek to reallocate some or all of any Section 743(b) adjustment we allocated to our tangible assets to goodwill instead. Goodwill, an intangible asset, is generally either nonamortizable or amortizable over a longer period of time or under a less accelerated method than our tangible assets. We cannot assure you that the determinations we make will not be successfully challenged by the IRS and that the deductions resulting from them will not be reduced or disallowed altogether. Should the IRS require a different basis adjustment to be made, and should, in our opinion, the expense of compliance exceed the benefit of the election, we may seek permission from the IRS to revoke our Section 754 election. If permission is granted, a subsequent purchaser of units may be allocated more income than he would have been allocated had the election not been revoked.

Tax Treatment of Operations

Accounting Method and Taxable Year. We use the year ending December 31 as our taxable year and the accrual method of accounting for federal income tax purposes. Each unitholder will be required to include in income his share of our income, gain, loss and deduction for our taxable year or

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years ending within or with his taxable year. In addition, a unitholder who has a taxable year different than our taxable year and who disposes of all of his units following the close of our taxable year but before the close of his taxable year must include his share of our income, gain, loss and deduction in income for his taxable year, with the result that he will be required to include in income for his taxable year his share of more than one year of our income, gain, loss and deduction. Please read "—Disposition of Common Units—Allocations Between Transferors and Transferees."

Tax Basis, Depreciation and Amortization. We use the tax basis of our assets for purposes of computing depreciation and cost recovery deductions and, ultimately, gain or loss on the disposition of these assets. The federal income tax burden associated with the difference between the fair market value of our assets and their tax basis immediately prior to an offering will be borne by our partners holding interests in us immediately prior to the time we issue units in an offering. Please read "—Tax Consequences of Unit Ownership—Allocation of Income, Gain, Loss and Deduction."

To the extent allowable, we may elect to use the depreciation and cost recovery methods that will result in the largest deductions being taken in the early years after assets subject to these allowances are placed in-service. Property we subsequently acquire or construct may be depreciated using accelerated methods permitted by the Internal Revenue Code.

If we dispose of depreciable property by sale, foreclosure or otherwise, all or a portion of any gain, determined by reference to the amount of depreciation previously deducted and the nature of the property, may be subject to the recapture rules and taxed as ordinary income rather than capital gain. Similarly, a unitholder who has taken cost recovery or depreciation deductions with respect to property we own will likely be required to recapture some or all of those deductions as ordinary income upon a sale of his interest in us. Please read "—Tax Consequences of Unit Ownership—Allocation of Income, Gain, Loss and Deduction" and "—Disposition of Common Units—Recognition of Gain or Loss."

The costs incurred in selling our units (called "syndication expenses") must be capitalized and cannot be deducted currently, ratably or upon our termination. There are uncertainties regarding the classification of costs as organization expenses, which we may be able to amortize, and as syndication expenses, which we may not amortize. The underwriting discounts and commissions we incur will be treated as syndication expenses.

Valuation and Tax Basis of Our Properties. The federal income tax consequences of the ownership and disposition of units will depend in part on our estimates of the relative fair market values, and the tax bases, of our assets. Although we may from time to time consult with professional appraisers regarding valuation matters, we will make many of the relative fair market value estimates ourselves. These estimates and determinations of basis are subject to challenge and will not be binding on the IRS or the courts. If the estimates of fair market value or basis are later found to be incorrect, the character and amount of items of income, gain, loss or deductions previously reported by unitholders might change, and unitholders might be required to adjust their tax liability for prior years and incur interest and penalties with respect to those adjustments.

Disposition of Common Units

Recognition of Gain or Loss. Gain or loss will be recognized on a sale of units equal to the difference between the unitholder's amount realized and the unitholder's tax basis for the units sold. A unitholder's amount realized will be measured by the sum of the cash or the fair market value of other property received by him plus his share of our non-recourse liabilities attributable to the common units sold. Because the amount realized includes a unitholder's share of our non-recourse liabilities, the gain recognized on the sale of units could result in a tax liability in excess of any cash received from the sale.

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Prior distributions from us in excess of cumulative net taxable income for a common unit that decreased a unitholder's tax basis in that common unit will, in effect, become taxable income if the common unit is sold at a price greater than the unitholder's tax basis in that common unit, even if the price received is less than his original cost.

Except as noted below, gain or loss recognized by a unitholder, other than a "dealer" in units, on the sale or exchange of a unit will generally be taxable as capital gain or loss. Capital gain recognized by an individual on the sale of units held more than twelve months will generally be taxed at a maximum U.S. federal income tax rate of 20 percent. In addition, all or a portion of the gain realized by a unitholder on the sale or exchange of a common unit, regardless of whether the common unit was held for more than twelve months, will generally by subject to a 3.8 percent Medicare tax. Please read "—Tax Consequences of Unit Ownership—Tax Rates." However, a portion, which will likely be substantial, of this gain or loss will be separately computed and taxed as ordinary income or loss under Section 751 of the Internal Revenue Code to the extent attributable to assets giving rise to depreciation recapture or other "unrealized receivables" or to "inventory items" we own. The term "unrealized receivables" includes potential recapture items, including depreciation recapture. Ordinary income attributable to unrealized receivables, inventory items and depreciation recapture may exceed net taxable gain realized on the sale of a unit and may be recognized even if there is a net taxable loss realized on the sale of a unit. Thus, a unitholder may recognize both ordinary income and a capital loss upon a sale of units. Net capital losses may offset capital gains and no more than $3,000 of ordinary income each year in the case of individuals and may only be used to offset capital gains in the case of corporations.

The IRS has ruled that a partner who acquires interests in a partnership in separate transactions must combine those interests and maintain a single adjusted tax basis for all those interests. Upon a sale or other disposition of less than all of those interests, a portion of that tax basis must be allocated to the interests sold using an "equitable apportionment" method. Treasury Regulations under Section 1223 of the Internal Revenue Code allow a selling unitholder who can identify common units transferred with an ascertainable holding period to elect to use the actual holding period of the common units transferred. Thus, according to the ruling discussed above, a common unitholder will be unable to select high or low basis common units to sell as would be the case with corporate stock, but, according to the Treasury Regulations, may designate specific common units sold for purposes of determining the holding period of units transferred. A unitholder electing to use the actual holding period of common units transferred must consistently use that identification method for all subsequent sales or exchanges of common units. A unitholder considering the purchase of additional units or a sale of common units purchased in separate transactions is urged to consult his tax advisor as to the possible consequences of this ruling and application of the Treasury Regulations.

Specific provisions of the Internal Revenue Code affect the taxation of some financial products and securities, including partnership interests, by treating a taxpayer as having sold an "appreciated" partnership interest, one in which gain would be recognized if it were sold, assigned or terminated at its fair market value, if the taxpayer or related persons enter(s) into:

•: a short sale;
•: an offsetting notional principal contract; or
•: a futures or forward contract with respect to the partnership interest or substantially identical property.

Moreover, if a taxpayer has previously entered into a short sale, an offsetting notional principal contract or a futures or forward contract with respect to the partnership interest, the taxpayer will be treated as having sold that position if the taxpayer or a related person then acquires the partnership interest or substantially identical property. The Secretary of the Treasury is also authorized to issue

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regulations that treat a taxpayer that enters into transactions or positions that have substantially the same effect as the preceding transactions as having constructively sold the financial position.

Allocations Between Transferors and Transferees. In general, our taxable income or loss will be determined annually, will be prorated on a monthly basis and will be subsequently apportioned among the unitholders in proportion to the number of units owned by each of them as of the opening of the applicable exchange on the first business day of the month, which we refer to in this prospectus as the "Allocation Date." However, gain or loss realized on a sale or other disposition of our assets other than in the ordinary course of business will be allocated among the unitholders on the Allocation Date in the month in which that gain or loss is recognized. As a result, a unitholder transferring units may be allocated income, gain, loss and deduction realized after the date of transfer.

Although simplifying conventions are contemplated by the Internal Revenue Code and most publicly traded partnerships use similar simplifying conventions, the use of this method may not be permitted under existing Treasury Regulations. The Department of the Treasury and the IRS have proposed Treasury Regulations that provide a safe harbor pursuant to which a publicly traded partnership may use a similar monthly simplifying convention to allocate tax items among transferor and transferee unitholders, although such tax items must be prorated on a daily basis. Nonetheless, the proposed regulations do not specifically authorize the use of the proration method we have adopted. Existing publicly traded partnerships are entitled to rely on these proposed Treasury Regulations; however, they are not binding on the IRS and are subject to change until final Treasury Regulations are issued. Accordingly, Andrews Kurth LLP is unable to opine on the validity of this method of allocating income and deductions between transferor and transferee unitholders. If this method is not allowed under the Treasury Regulations, or only applies to transfers of less than all of the unitholder's interest, our taxable income or losses might be reallocated among the unitholders. We are authorized to revise our method of allocation between transferor and transferee unitholders, as well as unitholders whose interests vary during a taxable year, to conform to a method permitted under future Treasury Regulations.

A unitholder who owns units at any time during a quarter and who disposes of them prior to the record date set for a cash distribution for that quarter will be allocated items of our income, gain, loss and deductions attributable to that quarter but will not be entitled to receive that cash distribution.

Notification Requirements. A unitholder who sells any of his units, other than through a broker, generally is required to notify us in writing of that sale within 30 days after the sale (or, if earlier, January 15 of the year following the sale). A purchaser of units who purchases units from another unitholder is also generally required to notify us in writing of that purchase within 30 days after the purchase. Upon receiving such notification, we are required to notify the IRS of that transaction and to furnish specified information to the transferor and transferee. Failure to notify us of a transfer of units may, in some cases, lead to the imposition of penalties. However, these reporting requirements do not apply to a sale by an individual who is a citizen of the U.S. and who effects the sale or exchange through a broker who will satisfy such requirements.

Constructive Termination. We will be considered to have been terminated for tax purposes if there are sales or exchanges which, in the aggregate, constitute 50% or more of the total interests in our capital and profits within a 12-month period. For purposes of measuring whether the 50% threshold is reached, multiple sales of the same interest are counted only once. A constructive termination results in the closing of our taxable year for all unitholders. In the case of a unitholder reporting on a taxable year different from our taxable year, the closing of our taxable year may result in more than 12 months of our taxable income or loss being includable in his taxable income for the year of termination. A constructive termination occurring on a date other than December 31 will result in us filing two tax returns (and unitholders could receive two Schedules K-1 if the relief discussed below is not available) for one fiscal year and the cost of the preparation of these returns will be borne by all common

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unitholders. We would be required to make new tax elections after a termination, including a new election under Section 754 of the Internal Revenue Code, and a termination would result in a deferral of our deductions for depreciation. A termination could also result in penalties if we were unable to determine that the termination had occurred. Moreover, a termination might either accelerate the application of, or subject us to, any tax legislation enacted before the termination. The IRS has announced a relief procedure whereby if a publicly traded partnership that has technically terminated requests and is granted relief from the IRS, among other things, the partnership will only have to provide one Schedule K-1 to unitholders for the fiscal year notwithstanding that two partnership tax years result from the termination.

Uniformity of Units

Because we cannot match transferors and transferees of units, we must maintain uniformity of the economic and tax characteristics of the units to a purchaser of these units. In the absence of uniformity, we may be unable to completely comply with a number of federal income tax requirements, both statutory and regulatory. A lack of uniformity can result from a literal application of Treasury Regulation Section 1.167(c)-1(a)(6). Any non uniformity could have a negative impact on the value of the units. Please read "—Tax Consequences of Unit Ownership—Section 754 Election."

We depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of Contributed Property, to the extent of any unamortized Book-Tax Disparity, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the unamortized Book-Tax Disparity of that property, or treat that portion as nonamortizable, to the extent attributable to property which is not amortizable, consistent with the Treasury Regulations under Section 743 of the Internal Revenue Code, even though that position may be inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6), which is not expected to directly apply to a material portion of our assets. Please read "—Tax Consequences of Unit Ownership—Section 754 Election." To the extent that the Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Book-Tax Disparity, we will apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may adopt a depreciation and amortization position under which all purchasers acquiring units in the same month would receive depreciation and amortization deductions, whether attributable to a common basis or Section 743(b) adjustment, based upon the same applicable methods and lives as if they had purchased a direct interest in our property. If this position is adopted, it may result in lower annual depreciation and amortization deductions than would otherwise be allowable to some unitholders and risk the loss of depreciation and amortization deductions not taken in the year that these deductions are otherwise allowable. This position will not be adopted if we determine that the loss of depreciation and amortization deductions will have a material adverse effect on the unitholders. If we choose not to utilize this aggregate method, we may use any other reasonable depreciation and amortization method to preserve the uniformity of the intrinsic tax characteristics of any units that would not have a material adverse effect on the unitholders.

Our counsel, Andrews Kurth LLP, is unable to opine on the validity of any of these positions. The IRS may challenge any method of depreciating the Section 743(b) adjustment described in this paragraph. If this challenge were sustained, the uniformity of units might be affected, and the gain from the sale of units might be increased without the benefit of additional deductions. We do not believe these allocations will affect any material items of income, gain, loss or deduction. Please read "—Disposition of Common Units—Recognition of Gain or Loss."

Tax-Exempt Organizations and Other Investors

Ownership of units by employee benefit plans, other tax-exempt organizations, regulated investment companies, non-resident aliens, foreign corporations and other foreign persons raises issues

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unique to those investors and, as described below, may have substantially adverse tax consequences to them.

Employee benefit plans and most other organizations exempt from federal income tax, including individual retirement accounts and other retirement plans, are subject to federal income tax on unrelated business taxable income. Virtually all of our income allocated to a unitholder that is a tax-exempt organization will be unrelated business taxable income and will be taxable to them.

A regulated investment company or "mutual fund" is required to derive 90 percent or more of its gross income from certain permitted sources. The American Jobs Creation Act of 2004 generally treats net income from the ownership of publicly traded partnerships as derived from such a permitted source. We anticipate that all of our net income will be treated as derived from such a permitted source.

Non-resident aliens and foreign corporations, trusts or estates that own units will be considered to be engaged in business in the U.S. because of the ownership of units. As a consequence, they will be required to file federal tax returns to report their share of our income, gain, loss or deduction and pay federal income tax at regular rates on their share of our net income or gain. Moreover, under rules applicable to publicly traded partnerships, we will withhold tax at the highest applicable effective tax rate from cash distributions made quarterly to foreign unitholders. Each foreign unitholder must obtain a taxpayer identification number from the IRS and submit that number to our transfer agent on a Form W-8BEN or applicable substitute form in order to obtain credit for these withholding taxes. A change in applicable law may require us to change these procedures.

In addition, because a foreign corporation that owns units will be treated as engaged in a U.S. trade or business, that corporation may be subject to the U.S. branch profits tax at a rate of 30 percent, in addition to regular federal income tax, on its share of our income and gain, as adjusted for changes in the foreign corporation's "U.S. net equity," that is effectively connected with the conduct of a U.S. trade or business. That tax may be reduced or eliminated by an income tax treaty between the U.S. and the country in which the foreign corporate unitholder is a "qualified resident." In addition, this type of unitholder is subject to special information reporting requirements under Section 6038C of the Internal Revenue Code.

Under a ruling published by the IRS, a foreign unitholder who sells or otherwise disposes of a unit will be subject to federal income tax on gain realized on the sale or disposition of that unit to the extent that this gain is effectively connected with a U.S. trade or business of the foreign unitholder. Because a foreign unitholder is considered to be engaged in a trade or business in the U.S. by virtue of the ownership of the common units, under this ruling, a foreign unitholder who sells or otherwise disposes of a unit generally will be subject to federal income tax on gain realized on the sale or other disposition of the common units. Apart from the ruling, a foreign unitholder will not be taxed or subject to withholding upon the sale or disposition of a unit if he has owned less than 5 percent in value of the units during the five-year period ending on the date of the disposition and if the units are regularly traded on an established securities market at the time of the sale or disposition.

Administrative Matters

Information Returns and Audit Procedures. We intend to furnish to each unitholder, within 90 days after the close of each taxable year, specific tax information, including a Schedule K-1, which describes each unitholder's share of our income, gain, loss and deduction for our preceding taxable year. In preparing this information, which will not be reviewed by counsel, we will take various accounting and reporting positions, some of which have been mentioned earlier, to determine each unitholder's share of income, gain, loss and deduction. We cannot assure you that those positions will in all cases yield a result that conforms to the requirements of the Internal Revenue Code, Treasury Regulations or administrative interpretations of the IRS. Neither we nor Andrews Kurth LLP can assure prospective

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unitholders that the IRS will not successfully contend in court that those positions are impermissible. Any challenge by the IRS could negatively affect the value of the units.

The IRS may audit our federal income tax information returns. Adjustments resulting from an IRS audit may require each unitholder to adjust a prior year's tax liability, and possibly may result in an audit of his return. Any audit of a unitholder's return could result in adjustments not related to our returns as well as those related to our returns.

Partnerships generally are treated as separate entities for purposes of federal income tax audits, judicial review of administrative adjustments by the IRS and tax settlement proceedings. The tax treatment of partnership items of income, gain, loss and deduction is determined in a partnership proceeding rather than in separate proceedings with the partners. The Internal Revenue Code requires that one partner be designated as the "Tax Matters Partner" for these purposes. The partnership agreement names our general partner as our Tax Matters Partner.

The Tax Matters Partner has made and will make some elections on our behalf and on behalf of unitholders. In addition, the Tax Matters Partner can extend the statute of limitations for assessment of tax deficiencies against unitholders for items in our returns. The Tax Matters Partner may bind a unitholder with less than a one percent profits interest in us to a settlement with the IRS unless that unitholder elects, by filing a statement with the IRS, not to give that authority to the Tax Matters Partner. The Tax Matters Partner may seek judicial review, by which all the unitholders are bound, of a final partnership administrative adjustment and, if the Tax Matters Partner fails to seek judicial review, judicial review may be sought by any unitholder having at least a 1 percent interest in profits or by any group of unitholders having in the aggregate at least a 5 percent interest in profits. However, only one action for judicial review will go forward, and each unitholder with an interest in the outcome may participate in that action.

A unitholder must file a statement with the IRS identifying the treatment of any item on his federal income tax return that is not consistent with the treatment of the item on our return. Intentional or negligent disregard of this consistency requirement may subject a unitholder to substantial penalties.

Nominee Reporting. Persons who hold an interest in us as a nominee for another person are required to furnish the following information to us:

(a) the name, address and taxpayer identification number of the beneficial owner and the nominee;

(b) a statement regarding whether the beneficial owner is:

1. a person that is not a U.S. person;

2. a foreign government, an international organization or any wholly owned agency or instrumentality of either of the foregoing; or

3. a tax-exempt entity;

(d) specific information including the dates of acquisitions and transfers, means of acquisitions and transfers, and acquisition cost for purchases, as well as the amount of net proceeds from sales.

Brokers and financial institutions are required to furnish additional information, including whether they are U.S. persons and specific information on units they acquire, hold or transfer for their own account. A penalty of $100 per failure, up to a maximum of $1.5 million per calendar year, is imposed

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by the Internal Revenue Code for failure to report that information to us. The nominee is required to supply the beneficial owner of the units with the information furnished to us.

Accuracy-Related Penalties. An additional tax equal to 20 percent of the amount of any portion of an underpayment of tax that is attributable to one or more specified causes, including negligence or disregard of rules or regulations, substantial understatements of income tax and substantial valuation misstatements, is imposed by the Internal Revenue Code. No penalty will be imposed, however, for any portion of an underpayment if it is shown that there was a reasonable cause for the underpayment of that portion and that the taxpayer acted in good faith regarding the underpayment of that portion.

For individuals, a substantial understatement of income tax in any taxable year exists if the amount of the understatement exceeds the greater of 10 percent of the tax required to be shown on the return for the taxable year or $5,000. The amount of any understatement subject to penalty generally is reduced if any portion is attributable to a position adopted on the return:

(1) for which there is, or was, "substantial authority"; or

(2) as to which there is a reasonable basis if the pertinent facts of that position are adequately disclosed on the return.

If any item of income, gain, loss or deduction included in the distributive shares of unitholders might result in that kind of an "understatement" of income for which no "substantial authority" exists, we must disclose the pertinent facts on our return. In addition, we will make a reasonable effort to furnish sufficient information for unitholders to make adequate disclosure on their returns to avoid liability for this penalty. More stringent rules apply to "tax shelters," but we believe we are not a tax shelter.

A substantial valuation misstatement exists if (a) the value of any property, or the adjusted basis of any property, claimed on a tax return is 150% or more of the amount determined to be the correct amount of the valuation or adjusted basis, (b) the price for any property or services (or for the use of property) claimed on any such return with respect to any transaction between persons described in Internal Revenue Code Section 482 is 200% or more (or 50% or less) of the amount determined under Section 482 to be the correct amount of such price, or (c) the net Internal Revenue Code Section 482 transfer price adjustment for the taxable year exceeds the lesser of $5 million or 10% of the taxpayer's gross receipts.

No penalty is imposed unless the portion of the underpayment attributable to a substantial valuation misstatement exceeds $5,000 ($10,000 for most corporations). If the valuation claimed on a return is 200% or more than the correct valuation, the penalty imposed increases to 40%. We do not anticipate making any valuation misstatements.

In addition, the 20% accuracy-related penalty also applies to any portion of an underpayment of tax that is attributable to transactions lacking economic substance. To the extent that such transactions are not disclosed, the penalty imposed is increased to 40%. Additionally, there is no reasonable cause defense to the imposition of this penalty to such transactions.

Reportable Transactions. If we were to engage in a "reportable transaction," we (and possibly you and others) would be required to make a detailed disclosure of the transaction to the IRS. A transaction may be a reportable transaction based upon any of several factors, including the fact that it is a type of tax avoidance transaction publicly identified by the IRS as a "listed transaction" or a "transaction of interest" or that it produces certain kinds of losses in excess of $2 million in any single year, or $4 million in any combination of six successive tax years. Our participation in a reportable transaction could increase the likelihood that our federal income tax information return (and possibly your tax return) would be audited by the IRS. Please read "—Information Returns and Audit Procedures" above.

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Moreover, if we were to participate in a reportable transaction with a significant purpose to avoid or evade tax, or in any listed transaction, you may be subject to the following additional consequences:

•: accuracy-related penalties with a broader scope, significantly narrower exceptions, and potentially greater amounts than described above at "—Accuracy-Related Penalties,"
•: for those persons otherwise entitled to deduct interest on federal tax deficiencies, nondeductibility of interest on any resulting tax liability, and
•: in the case of a listed transaction, an extended statute of limitations.

We do not expect to engage in any "reportable transactions."

Legislative Developments

The present U.S. 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. For example, from time to time, members of Congress propose and consider legislation that would affect publicly traded partnerships. Modification to the U.S. federal income tax laws and interpretations thereof may or may not be applied retroactively. Further, 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 or other forms of taxation. We are unable to predict whether such legislation, or other proposals, ultimately will be enacted. Any such changes could negatively impact the value of an investment in our common units.

State, Local and Other Tax Considerations

In addition to federal income taxes, you likely will be subject to other taxes, such as state and local income taxes, unincorporated business taxes, and estate, inheritance or intangible taxes that may be imposed by the various jurisdictions in which we do business or own property or in which you are a resident. Although an analysis of those various taxes is not presented here, each prospective unitholder should consider their potential impact on his investment in us. We own property or do business in 16 states, most of which impose income taxes. We may also own property or do business in other jurisdictions in the future. Although you may not be required to file a return and pay taxes in some jurisdictions if your income from that jurisdiction falls below the filing and payment requirement, you will be required to file income tax returns and to pay income taxes in many of these jurisdictions in which we do business or own property and may be subject to penalties for failure to comply with those requirements. In some jurisdictions, tax losses may not produce a tax benefit in the year incurred and may not be available to offset income in subsequent taxable years. Some of the jurisdictions may require us, or we may elect, to withhold a percentage of income from amounts to be distributed to a unitholder who is not a resident of the jurisdiction. Withholding, the amount of which may be greater or less than a particular unitholder's income tax liability to the jurisdiction, generally does not relieve a nonresident unitholder from the obligation to file an income tax return. Amounts withheld will be treated as if distributed to unitholders for purposes of determining the amounts distributed by us. Please read "—Tax Consequences of Unit Ownership—Entity-Level Collections." Based on current law and our estimate of our future operations, our general partner anticipates that any amounts required to be withheld will not be material.

It is the responsibility of each unitholder to investigate the legal and tax consequences, under the laws of pertinent jurisdictions, of his investment in us. Accordingly, each prospective unitholder is urged to consult, and depend on, his own tax counsel or other advisor with regard to those matters. Further, it is the responsibility of each unitholder to file all state and local, as well as U.S. federal tax returns, that may be required of him. Andrews Kurth LLP has not rendered an opinion on the state, local or foreign tax consequences of an investment in us.

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PLAN OF DISTRIBUTION

We may sell the common units (1) through agents, (2) through underwriters or dealers, (3) directly to one or more purchasers, or (4) pursuant to delayed delivery contracts or forward contracts.

By Agents

Common units may be sold through agents designated by us. Unless otherwise indicated in a prospectus supplement, the agents will agree to use their reasonable best efforts to solicit purchases for the period of their appointment.

By Underwriters

If underwriters are used in the sale, the common units of the series offered will be acquired by the underwriters for their own account. The underwriters may resell the common units in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the common units offered will be subject to certain conditions. The underwriters will be obligated to purchase all the common units offered if any of the securities are purchased. Any initial public offering price and any discounts or concessions allowed or re-allowed or paid to dealers may be changed from time to time.

Direct Sales

Common units may also be sold directly by us. In this case, no underwriters or agents would be involved. We may use electronic media, including the Internet, to sell offered securities directly.

Delayed Delivery Contracts or Forward Contracts

If indicated in the prospectus supplement, we will authorize agents, underwriters or dealers to solicit offers to purchase common units from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts or forward contracts providing for payment or delivery on a specified date in the future at prices determined as described in the prospectus supplement. Such contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth the commission payable for solicitation of such contracts.

General Information

Underwriters, dealers and agents that participate in the distribution of the common units may be underwriters as defined in the Securities Act, and any discounts or commissions received by them from us and any profit on the resale of the common units by them may be treated as underwriting discounts and commissions under the Securities Act. Any underwriters or agents will be identified and their compensation will be described in a prospectus supplement.

We may have agreements with the underwriters, dealers and agents to indemnify them against certain civil liabilities, including liabilities under the Securities Act, or to contribute with respect to payments which the underwriters, dealers or agents may be required to make because of those liabilities.

Underwriters, dealers and agents or their affiliates may engage in transactions with, or perform services for, us or our affiliates in the ordinary course of their businesses.

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LEGAL MATTERS

The validity of the securities being offered hereby will be passed upon for us by Andrews Kurth LLP, as our counsel.

EXPERTS

The financial statements as of December 31, 2012 and for the year ended December 31, 2012 and management's assessment of the effectiveness of internal control over financial reporting (which is included in Management's Report on Internal Control over Financial Reporting) as of December 31, 2012 incorporated in this registration statement and prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2012 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents incorporated in this prospectus by reference include, and each accompanying prospectus supplement may include, forward-looking statements. These forward-looking statements are identified as any statement that does not relate strictly to historical or current facts. They use words such as "anticipate," "believe," "intend," "plan," "projection," "forecast," "strategy," "position," "continue," "estimate," "expect," "may," or the negative of those terms or other variations of them or comparable terminology. In particular, statements, express or implied, concerning future actions, conditions or events, future operating results or the ability to generate sales, income or cash flow, to pay principal or interest on debt securities or to make distributions on common units are forward-looking statements. Forward-looking statements are not guarantees of performance. They involve risks, uncertainties and assumptions. Future actions, conditions or events and future results of operations may differ materially from those expressed in these forward-looking statements. Many of the factors that will determine these results are beyond our ability to control or predict. Specific factors which could cause actual results to differ from those in the forward-looking statements include:

•: the terms of sales on the drop-down of assets from KMI;
•: price trends and overall demand for natural gas in the United States;
•: economic activity, weather, alternative energy sources, conservation and technological advances that may affect price trends and demand;
•: changes in our tariff rates implemented by the Federal Energy Regulatory Commission;
•: our ability to acquire new businesses and assets and integrate those operations into our existing operations, as well as our ability to expand our facilities;
•: difficulties or delays experienced by ships in delivering products to our LNG terminal;
•: our ability to successfully identify and close acquisitions and make cost-saving changes in operations;
•: shut-downs or cutbacks at major refineries, petrochemical or chemical plants, ports, utilities, military bases or other businesses that could use our services or provide services or products to us;
•: changes in natural gas production from exploration and production areas that we serve;
•: changes in laws or regulations, third-party relations and approvals, and decisions of courts, regulators and governmental bodies that may adversely affect our business or our ability to compete;
•: changes in accounting standards that impact the measurement of our results of operations, the timing of when such measurements are to be made and recorded, and the disclosures surrounding these activities;
•: our ability to offer and sell equity securities and debt securities or obtain debt financing in sufficient amounts to implement that portion of our business plan that contemplates growth through acquisitions of operating businesses and assets and expansions of our facilities;
•: our indebtedness, which could make us vulnerable to general adverse economic and industry conditions, limit our ability to borrow additional funds, and/or place us at competitive disadvantages compared to our competitors that have less debt or have other adverse consequences;
•: interruptions of electric power supply to our facilities due to natural disasters, power shortages, strikes, riots, terrorism, war or other causes;

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•: our ability to obtain insurance coverage without significant levels of self-retention of risk;
•: acts of nature, accidents, sabotage, cyber attacks, terrorism or other similar acts causing damage greater than our insurance coverage limits;
•: capital and credit markets conditions, inflation and interest rates;
•: global political and economic stability;
•: national, international, regional and local economic, competitive and regulatory conditions and developments;
•: our ability to achieve cost savings and revenue growth;
•: the timing and extent of changes in natural gas commodity prices;
•: the ability to complete expansion projects on time and on budget;
•: the timing and success of our business development efforts; and
•: unfavorable results of litigation and the fruition of contingencies referred to in Note 10 to our consolidated financial statements included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2012.

Forward-looking statements are based on our expectations and beliefs concerning future events affecting us and are subject to uncertainties and factors related to our operations and business environment, all of which are difficult to predict and many of which are beyond our control. The foregoing list should not be construed to be exhaustive. Although we believe that the expectations reflected in our forward-looking statements are reasonable, we do not know whether our expectations will prove correct. Any or all of the forward-looking statements in this prospectus and any accompanying prospectus supplement may turn out to be wrong. They can be affected by inaccurate assumptions or by known or unknown risks and uncertainties. Many factors mentioned in this prospectus or any accompany prospectus supplement, including the risks outlined under the caption "Risk Factors" contained in our Exchange Act reports incorporated by reference, will be important in determining future results. Actual future results may vary materially. There is no assurance that the actions, events or results of the forward-looking statements will occur, or, if any of them do, when they will occur or what effect they will have on our results of operations or financial condition. In view of these uncertainties, we caution that investors should not place undue reliance on any forward-looking statements. Further, any forward-looking statement speaks only as of the date on which it is made, and, except as required by law, we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which it is made or to reflect the occurrence of anticipated or unanticipated events or circumstances.

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EL Paso Pipeline Partners (EPB) Inactive 424B5Prospectus supplement for primary offering