Marathon Petroleum runs 13 oil refineries across the United States with the capacity to process nearly 3 million barrels of crude oil every single day. It takes that raw crude, turns it into gasoline, diesel, jet fuel, asphalt, and dozens of other products, then sells them to gas station operators, wholesale customers, and exporters. It also owns MPLX, a pipeline and storage business that moves crude and finished fuels around the country, and it is building a growing renewable diesel operation at facilities in Dickinson, North Dakota and Martinez, California. The company earns money on the gap between what it pays for crude oil and what it charges for finished fuel, a gap the industry calls a crack spread. The diagram below traces where the money goes.
How Marathon Petroleum Makes Money
flowchart TD
A["Crude Oil Supply
2,787 mbpd"] --> B["Refining Capacity
2,986 mbpd"]
B --> C["Refined Products
3,023 mbpd output"]
C --> D["Product Sales
$116.5B revenue"]
D --> E["Operating Cash Flow
$8.3B"]
E --> F["Reinvestment in
Refining & Logistics"]
F --> B
C --> G["Renewable Diesel
1,114M gal/yr capacity"]
G --> H["Renewable Feedstock
Processing"]
H --> D
B --> I["Midstream Transport
Pipelines, Terminals, Barges"]
I --> J["Distribution to
7,882 Brand Outlets"]
J --> D
E --> K["Dividends &
Debt Service"]
K --> L["Shareholder Returns
and Liquidity"]
L -.->|Growth Capital| F
Five years of financial data tell a story of a business that can generate enormous cash when conditions line up, and then watch that cash shrink quickly when they do not. Revenue peaked at $177.5 billion in 2022, a year when fuel demand was strong and refining margins were wide. By 2025, revenue had fallen to $132.7 billion. That is not a small retreat. It reflects lower crude oil prices flowing through to lower product prices, which compress the numbers at the top of the income statement even when the company is refining more barrels than before.
Revenue 2021 to 2025 (USD billions)
Revenue peaked in 2022 and has declined each year since, driven by falling average refined product prices.
The gross margin tells a more revealing story than revenue alone. In 2021 the gross margin was just over 8 percent. It expanded to nearly 14.5 percent in 2022 when crack spreads were unusually wide. By 2024 it had compressed back down to about 9 percent, and it sat at roughly 10 percent in 2025. That compression happened even as the company processed more barrels. The refining & marketing margin per barrel fell from $23.00 in 2023 all the way to $16.01 in 2024, recovering only modestly to $16.87 in 2025. This is what a cyclical business looks like: the volume holds up reasonably well, but the profit per unit swings dramatically with market conditions the company cannot control.
What is a crack spread?
A crack spread is the difference between the price a refiner pays for crude oil and the price it receives when it sells finished products like gasoline and diesel. A wide crack spread means bigger profits per barrel. A narrow one squeezes margins even if the refinery is running flat out. Crack spreads change constantly based on global supply, seasonal demand, and geopolitical events, none of which refiners control.
Free cash flow followed the same arc. In 2022, the company generated $13.9 billion in free cash flow. By 2025 that had dropped to $4.8 billion. That is still a meaningful number, but it comes alongside net debt that has grown from $17.0 billion in 2022 to $26.8 billion in 2025. The Midstream segment has been expanding through acquisitions, including the $2.4 billion purchase of Northwind Midstream and the $703 million buyout of BANGL in 2025, and that expansion is partly responsible for the rising debt load. The Midstream business contributed $6.75 billion in segment adjusted EBITDA in 2025, and it receives long-term fee-based payments from the refining side of the business, which gives it more stable earnings than refining. But the growing debt is a number worth watching.
$26.8B
Net debt at end of 2025, up from $17.0B in 2022 as Midstream acquisitions accumulated
The Renewable Diesel segment is a different story. The company has invested in facilities that can produce renewable diesel from soybean oil, corn oil, fats, and greases, and it operates a 50/50 joint venture at the Martinez facility in California with Neste Corporation. That facility reached full capacity in late 2024. But the segment produced a loss of $110 million in segment adjusted EBITDA in 2025, following a loss of $150 million in 2024. The renewable diesel business generates regulatory credits called RINs and LCFS credits, which help offset compliance costs for the refining business, but as a standalone operation it has not yet turned profitable.
2021
milestone
Speedway sold to 7-Eleven for $21.38 billion
Marathon sold its entire Speedway convenience store chain and used the proceeds to concentrate entirely on refining, midstream, and renewable fuels. This reshaped the company's revenue mix permanently, removing a large retail business and making the refining margin the dominant driver of earnings.
The risks documented in the company's own filings are specific and serious. The most immediate is refining margin volatility. A single dollar change in the blended crack spread moves segment adjusted EBITDA by roughly $1.125 billion per year, according to the company's own sensitivity figures. That is a large lever in either direction. The second risk is structural: electric vehicles and tighter fuel efficiency rules from regulators are reducing demand for gasoline and diesel over time, and major car makers have committed to selling 40 to 50 percent electric vehicles by 2030. The third risk is geographic. California's Senate Bill SB X1-2 gives state regulators the power to set a maximum profit margin on gasoline and penalize refiners who exceed it. Marathon operates the Los Angeles refinery, the largest on the West Coast, and the Martinez facility in the same state. That law could directly cap what those assets earn.
$1.125B
Estimated change in annual Refining & Marketing adjusted EBITDA for every $1.00 per barrel move in the blended crack spread
What are RINs?
RINs stands for Renewable Identification Numbers. Federal law requires fuel producers to blend a certain amount of renewable fuel into their products each year. If a refiner does not produce enough renewable fuel itself, it must buy RINs on the open market as credits. Marathon spent $1.33 billion on purchased RINs in 2025 alone. RIN prices can spike without warning, and there is no official way to verify that most credits sold on the market are genuine.
Safety incidents are a documented financial risk, not just an operational concern. A fire at the Galveston Bay refinery in 2016 resulted in an $86 million settlement. A second fire broke out at the Garyville refinery in Louisiana in 2023, forcing nearby residents and schools to evacuate. The company operates refineries, pipelines, and tankers near populated areas and sensitive waterways, and it does not insure against all possible losses from these incidents. Any major accident could produce costs well beyond what insurance covers.
The Midstream segment collected $2.56 billion in limited partner distributions from MPLX during 2025. MPC owns approximately 64 percent of MPLX's common units, which had a market value of $34.55 billion at December 31, 2025. That stake is a significant asset sitting inside the consolidated company, and it generates recurring cash regardless of where refining margins happen to be in any given quarter.
$13.9B
Free cash flow 2022
$4.8B
Free cash flow 2025
Free cash flow fell by more than two-thirds from the 2022 peak to 2025 as crack spreads compressed and debt-funded Midstream acquisitions accumulated.
The Bet
Gasoline and diesel demand holds steady long enough, through the end of this decade and beyond, for Marathon's refining system to keep generating the cash that funds its Midstream expansion and its renewable diesel build-out, before those two businesses can fully carry themselves. If electric vehicle adoption accelerates faster than the company's own projections, or if California-style profit cap regulations spread to other states, or if crack spreads stay compressed for multiple years in a row, the cash engine that funds everything else shrinks before the newer, more resilient businesses are ready to replace it.
Open question
Marathon is simultaneously running one of the largest fossil fuel refining systems in the country, expanding a fee-based pipeline business through debt-funded acquisitions, and building a renewable diesel operation that is still losing money. Revenue has declined four years in a row from its 2022 peak, net debt has grown to $26.8 billion, and the company's single largest earnings driver can swing by more than $1 billion for every dollar move in a market price it cannot set. Can the Midstream and Renewable Diesel segments grow fast enough and become stable enough to cushion the business when the next refining downturn arrives, or does Marathon remain, at its core, a company whose fortunes rise and fall with a crack spread?
Compiled · 10-K · FY2025
Refining Margins Volatility
The company's profits depend heavily on the difference between what it pays for crude oil and what it sells refined products for. This gap changes unpredictably based on global supply, weather, competitor actions, and political events that the company cannot control. Big drops in these profit margins could force the company to cut production, reduce dividend payments, and write down asset values.
Demand for Petroleum Fuels
Electric vehicles and stricter fuel efficiency rules from the EPA and California are reducing demand for traditional gasoline and diesel. Major car makers have committed to selling 40 to 50 percent electric vehicles by 2030. If these trends accelerate faster than expected, the company could lose significant revenue from selling refined fuels.
California Refining Regulations
California's Senate Bill SB X1-2 gives regulators power to set a maximum profit margin on gasoline and penalize refiners who exceed it, plus control when refineries can do maintenance. The California Energy Commission is developing rules to enforce this, which could directly limit the company's profits at its Los Angeles and Martinez facilities.
Renewable Fuel Credit Costs
Federal law requires the company to blend renewable fuels into its products or buy credits (RINs) on the open market to comply. If credit prices spike or the company unknowingly purchases invalid credits, it could face substantial unexpected costs and penalties. There is no official way to verify most credits sold.
Operational Hazards and Environmental Liability
The company operates refineries, pipelines, and tankers that transport crude oil and refined products near populated areas and sensitive waters. Explosions, spills, or accidents could cause major damage, injury, environmental cleanup costs, and lawsuits. The company does not insure against all possible losses from these incidents.
10-K Item 1A · Risk Factors
