Oil refineries in the Gulf: why they matter

An oil refinery is a giant industrial plant that turns crude oil, which is not much use on its own, into products people actually buy: gasoline for cars, diesel for trucks and generators, jet fuel for planes, and raw materials for plastics. The Gulf is famous for pumping crude, but it also runs some of the largest refineries in the world. Refining lets Gulf countries earn more from their oil, fuel their own economies and supply their chemical industries. It is also why refineries have become targets during the 2026 regional war.

What a refinery does

Crude oil is a mix of many different hydrocarbons, from light gases to thick, tar-like material. A refinery separates and reshapes that mix in three broad stages.

• Separation. Crude is heated and fed into a tall tower called a distillation column. Lighter parts rise and are drawn off near the top, while heavier parts collect lower down.
• Conversion. Heavy leftovers are broken apart, or "cracked," using heat, pressure and chemical helpers called catalysts, turning them into lighter and more valuable fuels.
• Treatment. The products are cleaned, for example by removing sulfur, and blended to meet quality rules.

The exact mix of products depends on the refinery and on what customers want. As a rough guide, the US Energy Information Administration (EIA) says an average American refinery gets about 19 to 20 gallons of gasoline, 11 to 13 gallons of diesel-type fuel and 3 to 5 gallons of jet fuel from one 42-gallon barrel of crude.

Where the Gulf's biggest refineries are

Saudi Arabia has the region's largest refining system. The EIA put its domestic refining capacity at about 3.3 million barrels a day in 2023. Its main sites include the following.

• Ras Tanura, on the Gulf coast, the kingdom's biggest refinery, at about 550,000 barrels a day.
• Joint ventures with foreign oil companies, including SATORP in Jubail (with TotalEnergies), YASREF and SAMREF in Yanbu (with Sinopec and ExxonMobil), and Rabigh on the Red Sea (with Japan's Sumitomo).
• Jazan, in the southwest, at about 400,000 barrels a day.

Other Gulf countries have built big plants too. Kuwait's Al-Zour refinery runs at 615,000 barrels a day, which lifted Kuwait's total refining capacity to about 1.4 million barrels a day. Oman's Duqm refinery, a 230,000-barrel-a-day joint venture between Oman's OQ and Kuwait Petroleum International, pushed Oman's total above 500,000 barrels a day. The Ruwais refinery in Abu Dhabi also ranks among the largest in the Middle East.

Why Gulf countries refine their own oil

Selling crude straight from the ground is simpler, so why spend billions on refineries? There are four main reasons.

• More value per barrel. Fuels and chemical feedstocks usually sell for more than the crude used to make them, so refining keeps more of the earnings at home. This part of the oil industry is called downstream.
• Fuel for home use. Gulf countries use a lot of gasoline, diesel and fuel oil. Saudi Arabia, for example, burned about 1.4 million barrels a day of crude and fuel oil in power plants in June 2024, and oil produced 38% of its electricity in 2023, according to the EIA.
• Chemicals and jobs. Many Gulf refineries sit next to petrochemical plants that turn refinery products into plastics and fertilizers. This supports the region's diversification plans.
• Long-term partners. Joint ventures with Chinese, American, European and Japanese companies link big customers to Gulf oil for decades.

Refineries and processing plants are different

Not every oil site in the news is a refinery. Abqaiq, in eastern Saudi Arabia, is the world's biggest crude-processing plant. It cleans up raw crude so that it can be exported or sent to refineries, rather than turning it into fuels. That makes it one of the most important oil sites on Earth. When drones and missiles hit Abqaiq and the Khurais oil field in September 2019, about 5.7 million barrels a day of Saudi output was knocked out for a time. That was roughly half of the kingdom's production and about 5% of world supply.

How the 2026 war has hit Gulf refineries

This section reflects the situation in October 2026.

Saudi energy sites have faced several attacks and claimed attacks this year.

• March 2: Saudi Arabia halted some operations at Ras Tanura after an attack caused a fire, AFP reported.
• October 27: Yemen's Houthi movement said it hit Ras Tanura with a ballistic missile. Saudi authorities did not confirm the claim.
• October 30: The Houthis claimed attacks on the Ras Tanura and Rabigh refineries and the Abqaiq plant. Saudi-led forces said they intercepted a cruise missile aimed at western Saudi Arabia, Reuters reported.

Why refinery attacks move prices

Refinery problems affect markets in two ways. First, a refinery that stops working cannot supply gasoline, diesel or jet fuel, so fuel prices in the places it serves can rise even when crude is plentiful. Second, many refineries sit beside export terminals. Reuters notes that nearly all Saudi oil exports leave through Ras Tanura and Yanbu, so an attack near either site raises fears about crude supply as well. Brent crude rose 13.6% in October 2026 as attacks around the Gulf grew, according to Reuters. Even claims that cannot be checked quickly can move prices, because traders react to risk before all the facts are known.

Read next: How oil prices are set