Exhibit 99.1

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NEWS RELEASE

Phillips 66 announces agreement to purchase remaining interest in WRB Refining LP

HOUSTON, Sept. 9, 2025 – Phillips 66 (NYSE: PSX) announced today that it has entered into a definitive agreement to acquire the remaining 50% ownership interest in WRB Refining LP from subsidiaries of Cenovus Energy Inc. for total cash consideration of $1.4 billion, subject to customary purchase price adjustments.

WRB Refining LP is a 50/50 joint venture between Phillips 66 and Cenovus Energy Inc. that owns the Wood River refinery in Roxana, Illinois, and the Borger refinery in Borger, Texas. Phillips 66 has operated both facilities since the inception of the joint venture in 2007.

“With full ownership of the Wood River and Borger refineries, we are strengthening our integrated business and expanding our position in a region where we lead the industry,” said Mark Lashier, chairman and CEO of Phillips 66. “This acquisition is expected to deliver operational and commercial synergies of approximately $50 million per year by enabling full integration of these assets with the broader Phillips 66 value chain. We also expect this transaction to unlock opportunities for low-capital, high-return projects that provide incremental long-term shareholder value.”

The Wood River and Borger refineries have crude throughput capacities of 345 MBD and 149 MBD, respectively, reflecting a combined increase of approximately 250 MBD to Phillips 66’s refining capacity upon closing. The refineries can process heavy and medium sour crudes, as well as light sweet crudes. Both refineries also produce a high percentage of transportation fuels.

The transaction is expected to close during the fourth quarter of 2025.

About Phillips 66

Phillips 66 (NYSE: PSX) is a leading integrated downstream energy provider that manufactures, transports and markets products that drive the global economy. The company’s portfolio includes Midstream, Chemicals, Refining, Marketing and Specialties, and Renewable Fuels businesses. Headquartered in Houston, Phillips 66 has employees around the globe who are committed to safely and reliably providing energy and improving lives while pursuing a lower-carbon future. For more information, visit phillips66.com or follow @Phillips66Co on LinkedIn.

CONTACTS

Jeff Dietert (investors)

832-765-2297

jeff.dietert@p66.com

Owen Simpson (investors)

832-765-2297

owen.simpson@p66.com

Al Ortiz (media)

855-841-2368

al.s.ortiz@p66.com

Cautionary Statement for the Purposes of the “Safe Harbor” Provisions of the Private Securities Litigation Reform Act of 1995

— This news release contains forward-looking statements within the meaning of the federal securities laws relating to Phillips 66’s operations, strategy and performance. Words such as “anticipated,” “estimated,” “expected,” “planned,” “scheduled,” “targeted,” “believe,” “continue,” “intend,” “will,” “would,” “objective,” “goal,” “project,” “efforts,” “strategies” and similar expressions that convey the prospective nature of events or outcomes generally indicate forward-looking statements. However, the absence of these words does not mean that a statement is not forward-looking. Forward-looking statements included in this news release are based on management’s expectations, estimates and projections as of the date they are made. These statements are not guarantees of future events or performance, and you should not unduly rely on them as they involve certain risks, uncertainties and assumptions that are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed or forecast in such forward-looking statements. Factors that could cause actual results or events to differ materially from those described in the forward-looking statements include: changes in governmental policies relating to NGL, crude oil, natural gas, refined petroleum or renewable fuels products pricing, regulation or taxation, including exports; our ability to timely obtain or maintain permits, including those necessary for capital projects; fluctuations in NGL, crude oil, refined petroleum products, renewable fuels, renewable feedstocks and natural gas prices, and refined product, marketing and petrochemical margins; the effects of any widespread public health crisis and its negative impact on commercial activity and demand for our products; changes to government policies relating to renewable fuels and greenhouse gas emissions that adversely affect programs including the renewable fuel standards program, low carbon fuel standards and tax credits for biofuels; liability resulting from pending or future litigation or other legal proceedings; liability for remedial actions, including removal and reclamation obligations under environmental regulations; unexpected changes in costs or technical requirements for constructing, modifying or operating our facilities or transporting our products; our ability to successfully complete, or any material delay in the completion of, any asset disposition, acquisition, shutdown or conversion that we may pursue, including receipt of any necessary regulatory approvals or permits related thereto; unexpected technological or commercial difficulties in manufacturing, refining or transporting our products, including chemical products; the level and success of producers’ drilling plans and the amount and quality of production volumes around our midstream assets; risks and uncertainties with respect to the actions of actual or potential competitive suppliers and transporters of refined petroleum products, renewable fuels or specialty products; changes in the cost or availability of adequate and reliable transportation for our NGL, crude oil, natural gas and refined petroleum and renewable fuels products; failure to complete definitive agreements and feasibility studies for, and to complete construction of, announced and future capital projects on time or within budget; our ability to comply with governmental regulations or make capital expenditures to maintain compliance; limited access to capital or significantly higher cost of capital related to our credit profile or illiquidity or uncertainty in the domestic or international financial markets; damage to our facilities due to accidents, weather and climate events, civil unrest, insurrections, political events, terrorism or cyberattacks; domestic and international economic and political developments including armed hostilities, such as the war in Eastern Europe, instability in the financial services and banking sector, excess inflation, expropriation of assets and changes in fiscal policy, including interest rates; international monetary conditions and exchange controls; changes in estimates or projections used to assess fair value of intangible assets, goodwill and properties, plants and equipment and/or strategic decisions or other developments with respect to our asset portfolio that cause impairment charges; substantial investments required, or reduced demand for products, as a result of existing or future environmental rules and regulations, including greenhouse gas emissions reductions and reduced consumer demand for refined petroleum products; changes in tax, environmental and other laws and regulations (including alternative energy mandates) applicable to our business; political and societal concerns about climate change that could result in changes to our business or increase expenditures, including litigation-related expenses; the operation, financing and distribution decisions of our joint ventures that we do not control; the potential impact of activist shareholder actions or tactics; and other economic, business, competitive and/or regulatory factors affecting Phillips 66’s businesses generally as set forth in our filings with the U.S. Securities and Exchange Commission. Phillips 66 is under no obligation (and expressly disclaims any such obligation) to update or alter its forward-looking statements, whether as a result of new information, future events or otherwise.

Phillips 66 8-K