Marathon Petroleum Corporation is a downstream energy company headquartered at 539 South Main Street in Findlay, Ohio, where it also runs a corporate office alongside operations centres in the refining and midstream businesses. It operates the largest refining system in the United States and holds the general partner interest in MPLX, its sponsored midstream master limited partnership.
The 13-refinery system
The company reports crude oil refining capacity of approximately 3 million barrels per calendar day across 13 refineries, integrated with midstream assets and connected by transport links that allow intermediate products to move between plants. Published capacities and approximate employee numbers by site are:
- Galveston Bay, Texas: 631,000 barrels per calendar day
- Garyville, Louisiana: 617,000 barrels per calendar day
- Los Angeles, California: 365,000 barrels per calendar day
- Catlettsburg, Kentucky: 307,000 barrels per calendar day
- Robinson, Illinois: 253,000 barrels per calendar day, built in 1906 and bought by the company in 1924
- Detroit, Michigan: 146,000 barrels per calendar day, the only petroleum refinery in the state
- El Paso, Texas: 133,000 barrels per calendar day
- Anacortes, Washington: 119,000 barrels per calendar day
- St. Paul Park, Minnesota: 105,000 barrels per calendar day
- Canton, Ohio: 100,000 barrels per calendar day
- Mandan, North Dakota: 72,000 barrels per calendar day, operating since 1954
- Salt Lake City, Utah: 70,000 barrels per calendar day, operating since 1908
- Kenai, Alaska: 68,000 barrels per calendar day
Midstream through MPLX
The midstream segment is primarily the operations of MPLX, which gathers, transports, stores and distributes crude oil and refined products including renewable diesel through refining logistics assets, pipelines, terminals, towboats and barges. It also gathers, processes and transports natural gas and handles natural gas liquids through processing, fractionation, storage and marketing. MPLX owns crude oil and refined product pipelines, an inland marine business, light-product terminals, storage caverns, refinery tanks, docks and loading racks, plus gathering systems and processing facilities in United States supply basins.
Retail, industrial products and marine
Marathon brand and ARCO service stations operate across the United States and northern Mexico, supported by a rewards programme. The company also sells industrial petroleum products including asphalt and petrochemicals, and operates a global marine business. Retail customer feedback is routed to the Marathon and ARCO brand contact channels.
Sustainability, safety and 2026 milestones
Marathon Petroleum published a 2025 Sustainability Report and a 2026 climate-related scenarios report prepared with MPLX. In 2025 six of its refineries earned ENERGY STAR certifications from the United States Environmental Protection Agency for energy efficiency in the top quartile of similar facilities, and in September 2026 the Findlay corporate headquarters itself received ENERGY STAR certification. Company news through September 2026 covers rail safety, the extension of its sponsorship of the Cleveland Guardians baseball franchise and refinery-level energy performance.
Investors and contact
Marathon Petroleum trades on the New York Stock Exchange under the ticker MPC and has scheduled its third-quarter 2026 financial results conference call for Tuesday 3 November 2026 at 11:00 a.m. Eastern Time. Headquarters telephone is +1 419-422-2121 and investor relations can be reached on (419) 421-2071. Corporate communications handles media enquiries on (419) 421-3577, and the company publishes a media relations e-mail address and a set of downloadable corporate logos for editorial use.