Underwriting Agreement

Exhibit 10.1

Execution Version

$250,000,000 MAGELLAN MIDSTREAM PARTNERS, L.P.

6.400% Senior Notes due 2037

UNDERWRITING AGREEMENT

April 12, 2007

WACHOVIA CAPITAL MARKETS, LLC

CITIGROUP GLOBAL MARKETS INC.

J.P. MORGAN SECURITIES INC.

LAZARD CAPITAL MARKETS LLC

LEHMAN BROTHERS INC.

SUNTRUST CAPITAL MARKETS, INC.

c/o Wachovia Capital Markets, LLC

301 South College Street

Charlotte, North Carolina 28288-0613

c/o Citigroup Global Markets Inc.

388 Greenwich Street

New York, NY 10013

Dear Sirs:

Magellan Midstream Partners, L.P., a Delaware limited partnership (the " Partnership" ), proposes to issue and sell to the several underwriters named in Schedule 1 hereto (collectively, the " Underwriters" ) $250,000,000 aggregate principal amount of its 6.400% Senior Notes due 2037 (the " Notes" ) to be issued pursuant to the terms of an indenture (the " Original Indenture" ) between the Partnership and U.S. Bank National Association, as trustee (the " Trustee" ), to be dated as of the Delivery Date (as defined in Section 3 ), as supplemented by the First Supplemental Indenture to be dated as of the Delivery Date (the " Supplemental Indenture" ). The Original Indenture, as so supplemented, is referred to herein as the " Indenture ." Wachovia Capital Markets, LLC and Citigroup Global Markets Inc. shall act as representatives (the " Representatives" ) of the several Underwriters. Capitalized terms used but not defined herein shall have the same meanings given them in the Partnership Agreement (as defined herein).

Magellan GP, LLC, a Delaware limited liability company, serves as the general partner (the " General Partner" ) of the Partnership. The Partnership is the sole limited partner of Magellan OLP, L.P., a Delaware limited partnership (the " Operating Partnership" ), and the sole member of Magellan Operating GP, LLC, a Delaware limited liability company (" OLP GP" ), which serves as the general partner of the Operating Partnership. The Partnership is also the sole limited partner of Magellan Pipeline Company, L.P., a Delaware limited partnership (" MPL LP" ), Magellan Pipeline Terminals, L.P., a Delaware limited partnership (" MPT LP" ), and the sole member of Magellan Pipeline GP, LLC, a Delaware limited liability company (" MPGP LLC" ), which serves as the general partner of MPL LP and MPT LP. Each of Magellan NGL, LLC, a Delaware limited liability company (" MNGL LLC" ), Magellan Terminals Holdings,


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L.P., a Delaware limited partnership (" MTH LP" ), Magellan Pipelines Holdings, L.P., a Delaware limited partnership (" MPH LP" ), Magellan Ammonia Pipeline, L.P., a Delaware limited partnership (" MAP LP" ), and Magellan Asset Services, L.P., a Delaware limited partnership (" MAS LP" ), is a subsidiary of the Operating Partnership, and is sometimes referred to herein individually as a " Subsidiary" and collectively as the " Subsidiaries ." The Operating Partnership also owns a 50% limited liability company interest in Osage Pipe Line Company, LLC, a Delaware limited liability company (" Osage" ).

The Partnership, the General Partner, the Operating Partnership, OLP GP, MPL LP, MPT LP, MPGP LLC and the Subsidiaries are sometimes referred to herein individually as a " Partnership Entity" and collectively as the " Partnership Entities ." The Partnership Entities, excluding the General Partner, are sometimes referred to herein collectively as the " Partnership Group ." The Partnership, the General Partner, the Operating Partnership, OLP GP, MPL LP, MPT LP and MPGP LLC are sometimes referred to herein collectively as the " Magellan Parties ."

This underwriting agreement (this " Agreement" ) is to confirm the agreement among the Magellan Parties and the Underwriters concerning the purchase of the Notes from the Partnership by the Underwriters. Section 1. Representations, Warranties and Agreements of the Partnership Entities . The Magellan Parties, jointly and severally, represent, warrant and agree that: (a) Registration . A registration statement on Form S-3 (File No. 333-137166) with respect to certain securities, including the Notes, has (i) been prepared by the Partnership in conformity with the requirements of the Securities Act of 1933, as amended (the " Securities Act" ), and the rules and regulations (the " Rules and Regulations" ) of the Securities and Exchange Commission (the " Commission" ) thereunder; (ii) been filed with the Commission under the Securities Act; and (iii) become effective under the Securities Act. Copies of such registration statement and any amendment thereto have been delivered by the Partnership to the Representatives. As used in this Agreement:

(i) " Applicable Time" means 3:09 p.m. (New York City time) on the date of this Agreement, which the Underwriters have informed the Partnership is a time prior to the time of the first sale of the Notes; (ii) " Effective Date" means any date as of which any part of such registration statement relating to the Notes became, or is deemed to have become, effective under the Securities Act in accordance with the Rules and Regulations;

(iii) " Issuer Free Writing Prospectus" means each " free writing prospectus" (as defined in Rule 405 of the Rules and Regulations) prepared by or on behalf of the Partnership or used or referred to by the Partnership in connection with the offering of the Notes, including the final term sheet prepared pursuant to Section 4(b) hereof and attached to this Agreement in Annex 1 hereto; (iv) " Preliminary Prospectus" means any preliminary prospectus relating to the Notes included in such registration statement or filed with the Commission pursuant to


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Rule 424(b) of the Rules and Regulations, including any preliminary prospectus supplement thereto relating to the Notes; (v) " Pricing Disclosure Package" means, as of the Applicable Time, the most recent Preliminary Prospectus, together with each Issuer Free Writing Prospectus filed or used by the Partnership on or before the Applicable Time, other than a road show that is an Issuer Free Writing Prospectus under Rule 433 of the Rules and Regulations; (vi) " Prospectus" means the final prospectus relating to the Notes, including any prospectus supplement thereto, as filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations; and

(vii) " Registration Statement" means, collectively, the various parts of the registration statement on Form S-3 (File No. 333-137166), each as amended as of the Effective Date for such part, including any Preliminary Prospectus or the Prospectus and all exhibits to such registration statement.

Any reference in this Agreement or the exhibits or annexes hereto to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents incorporated by reference therein pursuant to Form S-3 under the Securities Act as of the date of the Registration Statement, such Preliminary Prospectus or the Prospectus, as the case may be. Any reference to the " most recent Preliminary Prospectus" shall be deemed to refer to the latest Preliminary Prospectus included in the Registration Statement or filed pursuant to Rule 424(b) prior to or on the date hereof (including, for purposes hereof, any documents incorporated by reference therein prior to or on the date hereof). Any reference to any amendment or supplement to any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any document filed under the Securities Exchange Act of 1934, as amended (the " Exchange Act" ), after the date of such Preliminary Prospectus or the Prospectus, as the case may be, and incorporated by reference in such Preliminary Prospectus or the Prospectus, as the case may be; and any reference to any amendment to the Registration Statement shall be deemed to include any periodic or current report of the Partnership filed with the Commission pursuant to Section 13(a) or 15(d) of the Exchange Act after the Effective Date that is incorporated by reference in the Registration Statement. The Commission has not issued any order preventing or suspending the use of any Preliminary Prospectus, the Prospectus or any Issuer Free Writing Prospectus or suspending the effectiveness of the Registration Statement, and no proceeding for such purpose has been instituted or threatened by the Commission. The Commission has not notified the Partnership of any objection to the use of the form of the Registration Statement.

(b) Well-Known Seasoned Issuer . The Partnership was, (i) at the time of filing of the Registration Statement and (ii) at the time of the most recent amendment thereto (whether by post-effective amendment, incorporated report filed pursuant to Section 13 or 15(d) of the Exchange Act, or form of prospectus) for purposes of complying with Section 10(a)(3) of the Securities Act (or, if any such amendment was not made within the time period required by Section 10(a)(3) of the Securities Act, at the date on which such amendment was required), a " well-known seasoned issuer" (as defined in Rule 405 of the Rules and Regulations). The Registration Statement is an " automatic shelf registration statement" (as defined in Rule 405 of the Rules and Regulations) and was filed not earlier than the date that is three years prior to the


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Delivery Date. The Partnership was not at the time of initial filing of the Registration Statement and at the earliest time thereafter that the Partnership or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) of the Rules and Regulations) of the Notes, and will not be on the Delivery Date, an " ineligible issuer" (as defined in Rule 405 of the Rules and Regulations).

(c) Form of Documents . The Registration Statement conformed and will conform in all material respects on the Effective Date and on the Delivery Date, and any amendment to the Registration Statement filed after the date hereof will conform in all material respects when filed, to the requirements of the Securities Act and the Rules and Regulations. The Preliminary Prospectus conformed, and the Prospectus will conform, in all material respects when filed with the Commission pursuant to Rule 424(b) and on the Delivery Date to the requirements of the Securities Act and the Rules and Regulations. The documents incorporated by reference in any Preliminary Prospectus or the Prospectus conformed, and any further documents so incorporated will conform, when filed with the Commission, in all material respects to the requirements of the Exchange Act or the Securities Act, as applicable, and the rules and regulations of the Commission thereunder.

(d) Registration Statement . The Registration Statement did not, as of the Effective Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; and each of the statements made by the Partnership in the Registration Statement and any further amendments to the Registration Statement within the coverage of Rule 175(b) of the Rules and Regulations, including (but not limited to) any statements with respect to future cash distributions of the Partnership or the anticipated ratio of taxable income to distributions was made with a reasonable basis and in good faith; provided that no representation or warranty is made as to information contained in or omitted from the Registration Statement in reliance upon and in conformity with written information furnished to the Partnership through the Representatives by or on behalf of any Underwriter specifically for inclusion therein, which information is specified in Section 7(e) .

(e) Prospectus . The Prospectus will not, as of its date or on the Delivery Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; and each of the statements made or to be made by the Partnership in the Preliminary Prospectus or the Prospectus, as applicable, and any further supplements to the Preliminary Prospectus or the Prospectus within the coverage of Rule 175(b) of the Rules and Regulations, including (but not limited to) any statements with respect to future cash distributions of the Partnership or the anticipated ratio of taxable income to distributions was made with a reasonable basis and in good faith; provided that no representation or warranty is made as to information contained in or omitted from the Prospectus in reliance upon and in conformity with written information furnished to the Partnership through the Representatives by or on behalf of any Underwriter specifically for inclusion therein, which information is specified in Section 7(e) .

(f) Documents Incorporated by Reference . The documents incorporated by reference in the Registration Statement, any Preliminary Prospectus or the Prospectus, when they were filed with the Commission and on the Delivery Date, conformed and will conform in all


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material respects to the requirements of the Exchange Act and the rules and regulations of the Commission thereunder and any further documents filed with the Commission and incorporated by reference in the Registration Statement, any Preliminary Prospectus or the Prospectus, when filed with the Commission and on the Delivery Date, will conform in all material respects to the requirements of the Exchange Act and the rules and regulations of the Commission thereunder. The documents incorporated by reference in the Registration Statement, any Preliminary Prospectus or the Prospectus did not, and any further documents filed and incorporated by reference therein will not, when filed with the Commission and on the Delivery Date, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(g) Pricing Disclosure Package . The Pricing Disclosure Package did not, as of the Applicable Time, contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that no representation or warranty is made as to information contained in or omitted from the Pricing Disclosure Package in reliance upon and in conformity with written information furnished to the Partnership through the Representatives by or on behalf of any Underwriter specifically for inclusion therein, which information is specified in Section 7(e) .

(h) Issuer Free Writing Prospectus and Pricing Disclosure Package . Each Issuer Free Writing Prospectus (including, without limitation, any road show that is a free writing prospectus under Rule 433 of the Rules and Regulations), when considered together with the Pricing Disclosure Package as of the Applicable Time, did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(i) Each Issuer Free Writing Prospectus . Each Issuer Free Writing Prospectus conformed or will conform in all material respects to the requirements of the Securities Act and the Rules and Regulations on the date of first use, and the Partnership has complied with any filing requirements applicable to such Issuer Free Writing Prospectus pursuant to the Rules and Regulations. The Partnership has not made any offer relating to the Notes that would constitute an Issuer Free Writing Prospectus without the prior written consent of the Representatives, except as set forth on Annex 2 hereto. The Partnership has retained in accordance with the Rules and Regulations all Issuer Free Writing Prospectuses that were not required to be filed pursuant to the Rules and Regulations (it being understood that, as of the date hereof, the Partnership has not retained any Issuer Free Writing Prospectus for the three year period required thereby). (j) Formation and Qualification of the Magellan Partnerships . Each of the Partnership, the Operating Partnership, MPL LP, MPT LP, MTH LP, MPH LP, MAP LP, MAS LP and Magellan IDR, L.P., a Delaware limited partnership (" IDR LP" ) has been duly formed and is validly existing in good standing as a limited partnership under the Delaware Revised Uniform Limited Partnership Act (the " Delaware LP Act" ), has full partnership power and authority necessary to own or hold its properties and assets and to conduct the businesses in which it is engaged, and is duly registered or qualified to do business as a foreign limited


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partnership in each jurisdiction set forth opposite its name on Annex 3 hereto, and such jurisdictions constitute all of the jurisdictions, with respect to each of the Partnership, the Operating Partnership, MPL LP, MPT LP, MTH LP, MPH LP, MAP LP, MAS LP and IDR LP, in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so register or qualify would not (i) have a material adverse effect on the condition (financial or other), business, prospects, properties, securityholders' equity or results of operations of the Partnership Group, taken as a whole, or (ii) subject the limited partners of the Partnership to any material liability or disability.

(k) Formation and Qualification of the Magellan Limited Liability Companies . Each of the General Partner, OLP GP, MPGP LLC, MNGL LLC, Magellan IDR LP, LLC, a Delaware limited liability company (" IDR LLC" ) and Osage has been duly formed and is validly existing in good standing as a limited liability company under the Delaware Limited Liability Company Act (the " Delaware LLC Act" ), has full limited liability company power and authority necessary to own or hold its properties and to conduct the businesses in which it is engaged, and is duly registered or qualified to do business as a foreign limited liability company in each jurisdiction set forth opposite its name on Annex 3 hereto, and such jurisdictions constitute all of the jurisdictions, with respect to each of the General Partner, OLP GP, MPGP LLC, MNGL LLC, IDR LLC and Osage, in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so register or qualify would not (i) have a material adverse effect on the condition (financial or other), business, prospects, properties, securityholders' equity or results of operations of the Partnership Group, taken as a whole, or (ii) subject the limited partners of the Partnership to any material liability or disability.

(l) [Intentionally Omitted.]

(m) Ownership of Interests; Subsidiaries . Other than (i) the General Partner' s ownership of the 1.995% general partner interest in the Partnership, a 100% membership interest in IDR LLC and a 0.001% general partner interest in IDR LP, (ii) the Partnership' s ownership of 100% of the member interests in MPGP LLC, 100% of the member interest of OLP GP, a 99.999% limited partner interest in the Operating Partnership, a 99.999% limited partner interest in each of MPL LP and MPT LP, (iii) OLP GP' s ownership of a 0.001% general partner interest in the Operating Partnership, (iv) MPGP LLC' s ownership of a 0.001% general partner interest in each of MPL LP and MPT LP, (v) the Operating Partnership' s ownership of a 99.999% limited partner interest in each of MAP LP, MTH LP, MPH LP and MAS LP, 100% of the member interests in MNGL LLC and 50% of the member interests in Osage and (vi) MNGL LLC' s ownership of a 0.001% general partner interest in each of MAP LP, MTH LP, MPH LP and MAS LP, none of the Partnership Entities own and, at the Delivery Date, will own, directly or indirectly, any equity of any corporation, partnership, limited liability company, joint venture, association or other entity; and none of these entities, other than the Operating Partnership, MPL LP and MTH LP, is a " significant subsidiary" of the Partnership as such term is defined in Rule 405 of the Rules and Regulations. (n) Ownership of the General Partner Interest in the Partnership . The General Partner is the sole general partner of the Partnership with a 1.995% general partner interest in the Partnership; such general partner interest has been duly and validly authorized and issued in accordance with the agreement of limited partnership of the Partnership (as the same may be


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amended or restated on or prior to the Delivery Date, the " Partnership Agreement" ); and the General Partner owns such general partner interest free and clear of all liens, encumbrances, security interests, equities, charges or claims (collectively, " Liens" ).

(o) Ownership of the Incentive Distribution Rights and Outstanding Units . As of the Applicable Time and the date of the Prospectus, the Partnership has no limited partner interests issued and outstanding other than the following:

(i) the Incentive Distribution Rights (as defined in the Partnership Agreement) held by IDR LP; and (ii) 66,546,297 Common Units held by public unitholders,

all of such Incentive Distribution Rights and Common Units and the limited partner interests represented thereby have been duly authorized and validly issued in accordance with the Partnership Agreement and are fully paid (to the extent required under the Partnership Agreement) and nonassessable (except as such nonassessability may be affected by Section 17-607 of the Delaware LP Act); and the General Partner owns all of such Incentive Distribution Rights, free and clear of all Liens.

(p) Authority. Each of the Magellan Parties has full right, power and authority to execute and deliver this Agreement and to perform its obligations hereunder; the Partnership has full right, power and authority to execute and deliver the Notes, the Original Indenture and the Supplemental Indenture and to perform its obligations thereunder (this Agreement, the Notes, the Original Indenture and the Supplemental Indenture, are each referred to herein individually as a " Debt Document" and collectively as the " Debt Documents" ). On the Delivery Date, all corporate, partnership and limited liability company action, as the case may be, required to be taken by the Magellan Parties, or any of their securityholders, partners or members for (i) the authorization, issuance, sale and delivery of the Notes, (ii) the execution and delivery of the Debt Documents and (iii) the consummation of the transactions contemplated by the Debt Documents, shall have been validly taken. (q) Authorization and Enforceability of the Indenture. The Indenture has been duly qualified under the Trust Indenture Act of 1939, as amended (the " Trust Indenture Act" ), and as of the Delivery Date, the Indenture will be duly authorized, executed and delivered by the Partnership and will constitute a valid and legally binding agreement of the Partnership enforceable against the Partnership in accordance with its terms, except as enforceability may be limited by the Enforceability Exceptions (as defined in Section 1(cc) herein). (r) Valid Issuance of the Notes . The Notes have been duly authorized by the Partnership for issuance and sale to the Underwriters and, when duly executed, authenticated, issued and delivered as provided in the Indenture and paid for as provided herein, will be duly and validly issued and outstanding and will constitute valid and legally binding obligations of the Partnership enforceable against the Partnership in accordance with their terms, subject to the Enforceability Exceptions, and will be entitled to the benefits of the Indenture.

(s) Descriptions . Each Debt Document that is described in the Registration Statement, the Pricing Disclosure Package and the Prospectus conforms in all material respects


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to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus. (t) Ownership of OLP GP . The Partnership is the sole member of OLP GP with a 100% member interest in OLP GP; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of OLP GP (as the same may be amended or restated on or prior to the Delivery Date, the " OLP GP LLC Agreement" ), and is fully paid (to the extent required under the OLP GP LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Partnership owns such member interest free and clear of all Liens.

(u) Ownership of MPGP LLC . The Partnership is the sole member of MPGP LLC with a 100% member interest in MPGP LLC; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of MPGP LLC (as the same may be amended or restated on or prior to the Delivery Date, the " MPGP LLC Agreement" ), and is fully paid (to the extent required under the MPGP LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Partnership owns such member interest free and clear of all Liens.

(v) Ownership of the Operating Partnership . (i) OLP GP is the sole general partner of the Operating Partnership with a 0.001% general partner interest in the Operating Partnership; such general partner interest has been duly authorized and validly issued in accordance with the agreement of limited partnership of the Operating Partnership (as the same may be amended or restated on or prior to the Delivery Date, the " Operating Partnership Agreement" ); and the OLP GP owns such general partner interest free and clear of all Liens.

(ii) The Partnership is the sole limited partner of the Operating Partnership with a 99.999% limited partner interest in the Operating Partnership; such limited partner interest has been duly authorized and validly issued in accordance with the Operating Partnership Agreement and is fully paid (to the extent required under the Operating Partnership Agreement) and nonassessable (except as such nonassessability may be affected by Section 17-607 of the Delaware LP Act); and the Partnership owns such limited partner interest free and clear of all Liens.

(w) Ownership of MNGL LLC . The Operating Partnership is the sole member of MNGL LLC with a 100% member interest in MNGL LLC; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of MNGL LLC (as the same may be amended or restated on or prior to the Delivery Date, the " MNGL LLC Agreement" ), and is fully paid (to the extent required under the MNGL LLC Agreement) and nonassessable (except as such nonassessability may be affected by Section 18-607 of the Delaware LLC Act); and the Operating Partnership owns such member interest free and clear of all Liens.

(x) Ownership of the LP Subsidiaries .

(i) MNGL LLC is the sole general partner of each of MAP LP, MAS LP, MPH LP and MTH LP (the " LP Subsidiaries" ) with a 0.001% general partner interest in


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each of the LP Subsidiaries; each such general partner interest has been duly authorized and validly issued in accordance with each of the respective agreements of limited partnership of each of the LP Subsidiaries (as each may be amended and restated on or prior to the Delivery Date, the " LP Subsidiary Partnership Agreements" ); and MNGL LLC owns each such general partner interest free and clear of all Liens.

(ii) The Operating Partnership is the sole limited partner of each of the LP Subsidiaries with a 99.999% limited partner interest in each of the LP Subsidiaries; each such limited partner interest has been duly authorized and validly issued in accordance with each of the respective LP Subsidiary Partnership Agreements and is fully paid (to the extent required under each of the LP Subsidiary Partnership Agreements) and nonassessable (except as such nonassessability may be affected by Section 17-607 of the Delaware LP Act); and the Operating Partnership owns each of such limited partner interest free and clear of all Liens.

(y) Ownership of the General Partner . Magellan Midstream Holdings, L.P., a publicly traded Delaware limited partnership (" MGG" ), is the sole member of the General Partner with a 100% member interest in the General Partner; such member interest has been duly authorized and validly issued in accordance with the limited liability company agreement of the General Partner (as the same may be amended or restated on or prior to the Delivery Date, the " GP LLC Agreement" ), and is fully paid (to the extent required under the GP LLC Agreement) and nonassessable (except as such ...