MPLX LP : 4Q 2021 Earnings Release Slides–Feb 2, 2022

Fourth Quarter 2021

Earnings Conference Call

February 2, 2022

Forward‐Looking Statements

This presentation contains forward-looking statements regarding MPLX LP (MPLX). These forward-looking statements may relate to, among other things, MPLX's expectations, estimates and projections concerning its business and operations, financial priorities, including with respect to positive free cash flow and distribution coverage, strategic plans, capital return plans, operating cost and capital expenditure reduction objectives, and environmental, social and governance goals. You can identify forward-looking statements by words such as "anticipate," "believe," "commitment," "could," "design," "estimate," "expect," "forecast," "goal," "guidance," "imply," "intend," "may," "objective," "opportunity," "outlook," "plan," "policy," "position," "potential," "predict," "priority," "project," "proposition," "prospective," "pursue," "seek," "should," "strategy," "target," "will," "would" or other similar expressions that convey the uncertainty of future events or outcomes. MPLX cautions that these statements are based on management's current knowledge and expectations and are subject to certain risks and uncertainties, many of which are outside of the control of MPLX, that could cause actual results and events to differ materially from the statements made herein. Factors that could cause MPLX's actual results to differ materially from those implied in the forward-looking statements include but are not limited to: general economic, political or regulatory developments, including inflation, changes in governmental policies relating to refined petroleum products, crude oil, natural gas or NGLs, or taxation; the magnitude, duration and extent of future resurgences of the COVID-19 pandemic and its effects, including the continuation or re-imposition of travel restrictions, business and school closures, increased remote work, stay at home orders and other actions taken by individuals, government and the private sector to stem the spread of the virus; the adequacy of capital resources and liquidity, including the availability of sufficient free cash flow from operations to pay distributions and to fund future unit repurchases; the ability to access debt markets on commercially reasonable terms or at all; the timing and extent of changes in commodity prices and demand for crude oil, refined products, feedstocks or other hydrocarbon-based products; changes to the expected construction costs and timing of projects and planned investments, the availability of desirable strategic initiatives for the Alaska logistics and storage operations or other portfolio assets and the ability to obtain regulatory and other approvals with respect thereto; accidents or other unscheduled shutdowns affecting our machinery, pipelines, processing, fractionation and treating facilities or equipment, means of transportation, or those of our suppliers or customers; the suspension, reduction or termination of MPC's obligations under MPLX's commercial agreements; other risk factors inherent to MPLX's industry; the impact of adverse market conditions or other similar risks to those identified herein affecting MPC; and the factors set forth under the heading "Risk Factors" in MPLX's Annual Report on Form 10-K for the year ended Dec. 31, 2020, and in other filings with Securities and Exchange Commission (SEC).

Any forward-looking statement speaks only as of the date of the applicable communication and we undertake no obligation to update any forward-looking statement except to the extent required by applicable law.

Copies of MPLX's Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and other SEC filings are available on the SEC's website, MPLX's website at http://ir.mplx.com or by contacting MPLX's Investor Relations office. Copies of MPC's Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and other SEC filings are available on the SEC's website, MPC's website at https://www.marathonpetroleum.com/Investors/ or by contacting MPC's Investor Relations office.

Non-GAAP Financial Measures

Adjusted EBITDA, distributable cash flow (DCF), distribution coverage ratio and leverage ratio, free cash flow (FCF) and excess/deficit cash flow are non-GAAP financial measures provided in this presentation. Adjusted EBITDA, DCF, FCF and excess/deficit cash flow reconciliations to the nearest GAAP financial measures are included in the Appendix to this presentation. Distribution coverage ratio is the ratio of DCF attributable to GP and LP unitholders to total GP and LP distributions declared. Leverage ratio is consolidated debt to last twelve months pro forma adjusted EBITDA. These non-GAAP financial measures are not defined by GAAP and should not be considered in isolation or as an alternative to net income attributable to MPLX, net cash provided by operating activities or other financial measures prepared in accordance with GAAP. Certain EBITDA forecasts were determined on an EBITDA-only basis. Accordingly, information related to the elements of net income, including tax and interest, are not available and, therefore, reconciliations of these forward-lookingnon-GAAP financial measures to the nearest GAAP financial measures have not been provided.

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Business Update

• Solid operational performance, strict capital discipline, and low-cost culture
• Commitment to return of capital
• Continuing to evaluate natural gas, NGL, and low carbon opportunities

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2022 Capital Spending Outlook

• Continue strict capital discipline with $900MM capital spending outlook:
• • $700MM growth capital
  • $140MM maintenance capital
  • $60MM repayment of our share of the Bakken Pipeline JV debt due in 2022
• Focus on expansion and de-bottlenecking projects

Total Capex ($B)

$2.7

$2.5

$1.0$0.9

$0.6

2018	2019	2020	2021	2022
	Growth Capital	Maintenance Capital

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Capital Deployment Framework

Maintenance Capital

Distributions

Disciplined Growth Capital

Return of Capital

Strong balance sheet foundation for strategy execution

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