Magellan Midstream Partners L P : 2021 Proxy Statement

One Williams Center Tulsa, Oklahoma 74172

MICHAEL N. MEARS

CHAIRMAN OF THE BOARD, PRESIDENT

AND CHIEF EXECUTIVE OFFICER OF THE GENERAL PARTNER

February 18, 2021

To our Limited Partners:

You are cordially invited to attend the 2021 virtual annual meeting of limited partners of Magellan Midstream Partners, L.P. to be held via webcast on Thursday, April 22, 2021, commencing at 10:00 a.m. Central Time.

At this year's meeting, you will be asked to elect three Class I directors to our general partner's board of directors, approve an increase in the number of units authorized to be issued under our Long-Term Incentive Plan, approve an advisory resolution on our executive compensation and ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 2021. The board of directors of our general partner unanimously recommends you approve each of these proposals. I urge you to read our proxy statement for further details about the proposals.

On February 26, 2021, we will mail the Important Notice Regarding the Availability of Proxy Materials (the "Notice") to all unitholders of record at the close of business on February 16, 2021 and post our proxy materials on our website. As described in the Notice, you may request a printed set of the proxy materials, including our Annual Report and Form 10-K for the fiscal year ended December 31, 2020, if you do not wish to access the materials on our website. In addition, the Notice will provide information regarding how you may request to receive proxy materials by mail or by email on an ongoing basis.

Your vote is important to us and our business. Except on the independent auditor proposal, your broker cannot vote your units on your behalf until it receives your voting instructions. Whether or not you plan to attend the annual meeting, please cast your vote by following the internet or telephone voting instructions contained in the Notice. Alternatively, you may request a printed copy of the proxy materials and vote by mail by completing, signing and returning the proxy card. We look forward to your participation.

Sincerely,

Michael N. Mears

Notice of Annual Meeting of Limited Partners

To the Limited Partners of Magellan Midstream Partners, L.P.:

The annual meeting of limited partners of Magellan Midstream Partners, L.P. will be held via webcast on April 22, 2021 at 10:00 a.m. Central Time to consider the following matters:

• 1. The election of three Class I directors to our general partner's board of directors to serve until the 2024 annual meeting of limited partners;

• 2. The amendment of the Magellan Midstream Partners Long-Term Incentive Plan, as amended and restated, to increase the total number of common units authorized to be issued under the plan;

• 3. An advisory vote on executive compensation;

• 4. The ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 2021; and

• 5. The transaction of any other business as may properly come before the annual meeting or any adjournments thereof, including, without limitation, the adjournment of the annual meeting in order to solicit additional votes from unitholders with respect to the foregoing proposals.

Only unitholders of record at the close of business on February 16, 2021 are entitled to participate in and vote at the annual meeting or any recommencement thereof following any adjournments. The virtual annual meeting will be held atwww.meetingcenter.io/242022654. If you would like the ability to vote or ask questions during the meeting, when you join, you must enter the password MMP2021 and the control number found on your proxy card. If you hold units through a broker, bank or other nominee, you must register in advance if you wish to vote or ask questions during the meeting. To register, you must submit proof of ownership, along with your name and email address, to the Partnership's transfer agent, Computershare, [e-mail] 4:00 p.m. Central Time on April 16, 2021. You will then receive an email response from Computershare to confirm registration and provide a control number for use when joining the meeting. Any unitholder may access the event as a guest without the need for advance registration, but guests will not be able to vote or ask questions during the annual meeting.

Important Notice Regarding the Availability of Proxy Materials for our Annual Meeting to Be Held on April 22, 2021

This notice together with our proxy statement, form of proxy card and 2020 annual report are available atwww.magellanlp.com/Investors/SECFilings.aspx.

Date:

April 22, 2021

Time:

10:00 a.m. Central Time

Place:

Virtual

Record Date:

February 16, 2021

By Order of the Board of Directors of Magellan GP, LLC, general partner of

Magellan Midstream Partners, L.P.

Suzanne H. Costin Secretary

Tulsa, Oklahoma February 18, 2021

Your vote is important! Except on the independent auditor proposal, your broker cannot vote your units on your behalf until it receives your voting instructions. For your convenience, internet and telephone voting are available. The instructions for voting by internet or telephone are set forth in the Notice. If you prefer, you may request a printed copy of the proxy materials, including the proxy card, and vote by mail by completing, signing and returning the proxy card in a postage-paid envelope.

Internet

Telephone

Mail

During Meeting

Follow the instructions on the Notice to vote by internet.

Follow the instructions on the

Notice to vote by phone.

Complete your proxy card and return it by mail.

Attend and vote during the virtual Annual Meeting.

Table of Contents

Proxy Statement 1

Proposals 1 Outstanding Common Units Held on Record

Date 2

Quorum Required 2

Broker Non-Votes and Abstentions 2

How to Vote 2 Revoking Your Proxy or Changing Your Internet

or Telephone Vote 3

Solicitation and Mailing of Proxies 3

Other Matters for the 2021 Annual Meeting 4

Director Election Proposal 5

Board Diversity 5 Class I Director Nominees - If Elected, Term

Expires at the 2024 Annual Meeting of

Limited Partners 6

Class II Directors - Term Expires at the 2022

Annual Meeting of Limited Partners 7

Class III Directors - Term Expires at the 2023

Annual Meeting of Limited Partners 9

LTIP Amendment Proposal 11

Key Governance Provisions of the LTIP 11

Summary Description of the LTIP, as Amended 13

Certain Federal Income Tax Consequences 14

LTIP Awards 15

Executive Compensation Proposal 16

Independent Auditor Proposal 17

Audit Fees 17

Audit-Related Fees 17

Tax Fees 17

All Other Fees 17

Governance 19

Director Independence 19

Risk Oversight 19 Meetings of the Board of Directors and its

Committees 20

Board Committees 21

2020 Report of the Audit Committee 21

Director Nominations 22

Communications to our Board of Directors 23

Code of Ethics 23

Prohibition on Hedging 23

Executive Officers of Our General Partner 24

Compensation of Directors and Executive

Officers 26

Compensation Discussion and Analysis 26

Overview of our Executive Compensation 26

Unitholder Return Performance 28 Role of Unitholder "Say on Pay" Advisory

Votes 28

Role of the Compensation Committee 29

Role of the Compensation Consultant 29

Role of Management 30

2020 Executive Compensation 30 Executive Officer and Independent Director

Equity Ownership Guidelines 40

Retirement of Executive Officers 40

Deductibility of Executive Compensation 40

Compensation Committee Report 41

Summary Compensation Table 42

Grants of Plan-Based Awards 43 Narrative Disclosure to Summary

Compensation Table and Grants of

Plan-Based Awards Table 43 Outstanding Equity Awards at 2020 Fiscal

Year-End 44

Units Vested 45

2020 Pension Benefits 45 Potential Payments Upon Termination or

Change-in-Control 47

CEO Pay Ratio 48

Director Compensation Table 49

Narrative to Director Compensation Table 51

Securities Authorized for Issuance Under

Equity Compensation Plans 52

Security Ownership of Certain Beneficial

Owners and Management 53

Transactions with Related Persons,

Promoters and Certain Control Persons 54 Review, Approval or Ratification of

Transactions with Related Persons 54

Section 16(a) Beneficial Ownership Reporting

Compliance 54

Unitholder Proposals for 2022 Annual

Meeting of Limited Partners 54

Where You Can Find More Information

About Us 55

Annex A - Magellan Long-Term Incentive

Plan

A-1