Who’s Holding Strategic Oil Reserves, and How Much Can They Really Help?

The effective closure of the Strait of Hormuz after attacks and threats tied to the US-Israel conflict with Iran has disrupted around 20 percent of global crude oil and liquified natural gas flows. Prices jumped, with Brent crude topping $100 a barrel compared with roughly $65 before the fighting intensified. Countries and international bodies are now digging into emergency oil stores to calm markets.

Why are strategic oil reserves a thing?

A strategic oil reserve, or strategic petroleum reserve, is a government-held stockpile of crude oil kept for emergencies such as wars, sanctions or major supply shocks. Governments usually acquire this oil through deals with private companies and keep it in government-controlled facilities so it can be released when markets need it.

The International Energy Agency reports that its member countries hold more than 1.2 billion barrels of public emergency oil stocks, plus about 600 million barrels held by industry under government mandate. Non-IEA countries also keep large reserves, so the global picture is bigger than the IEA numbers alone.

What happened this month

On March 11, the 32 member countries of the IEA agreed to release a coordinated 400 million barrels from emergency reserves. That is the largest coordinated release in the agency’s history and much larger than the 182 million barrels released in 2022 following Russia’s invasion of Ukraine. The move is meant to steady markets while the Strait of Hormuz disruption continues and some Gulf producers cut output.

Who has the biggest reserves?

China

China is not an IEA member but is widely understood to hold the largest strategic stockpiles. Beijing started a state reserve program in 2004 and planned reserve bases designed to equal roughly 30 days of imports. Official disclosure is limited, but industry estimates vary. One energy analytics firm reported China’s onshore crude inventories reached a record level of about 1.13 billion barrels by the end of 2025, though that figure mixes commercial and strategic storage and is not an official government total.

Chinese refiners bought a very large share of Iran’s exported oil in 2025. As the Iran conflict tightened, some Chinese companies signaled they would avoid buying Iranian oil, and domestic firms asked the government to consider releasing stockpiles to keep refineries supplied.

United States

The United States maintains one of the largest official strategic petroleum reserves at about 415 million barrels. The reserves are managed by the Department of Energy and are located near major refining and petrochemical hubs. The system can move roughly 4.4 million barrels of oil per day to the market.

The US has committed to release 172 million barrels from its reserve over the year as part of the IEA coordination, and has already lent 45.2 million barrels to oil companies. The US reserve was created in 1975 after an earlier oil supply shock and normally represents many weeks of net import coverage. A Reuters calculation put current coverage at roughly 200 days of net crude imports.

Japan

Japan is an IEA member and holds sizeable emergency stockpiles. At the end of 2025 the country had about 470 million barrels in reserve, which was equivalent to about 254 days of domestic consumption. That total includes government-owned stock, industry-held stock under mandate, and jointly stored volumes with producers.

Japan began releasing oil from its emergency stores amid the recent supply concerns. Officials described a significant unilateral release to support domestic supply and to contribute to wider market stability.

United Kingdom

The UK keeps strategic stocks too. As of late February, the country reported around 38 million barrels of crude and another 30 million barrels of refined products held to meet emergency needs. The system is designed to meet a 90-day net import requirement set by international obligations. The UK is part of the IEA release and will contribute about 13.5 million barrels to the coordinated drawdown.

Selected European holdings

• Germany: The economy ministry reports about 110 million barrels of crude and 67 million barrels of finished petroleum products available for release if needed.
• France: At the end of 2024 France reported roughly 120 million barrels of crude and finished products in reserve, with the bulk held by a state-mandated entity and the rest by oil operators. The mix includes crude, gasoil, gasoline, jet fuel and some heating oil.
• Spain: Spain approved a release of about 11.5 million barrels to be delivered over 90 days as part of the IEA action. Total national reserves are on the order of 150 million barrels.
• Italy: By law Italy maintains reserves equivalent to about 90 days of average net imports, which was roughly 76 million barrels in 2024.

Can these reserves handle the disruption?

Strategic reserves are intended to smooth short-term shocks, not replace long-term lost production. The IEA coordinated release of 400 million barrels is the biggest collective move yet and should provide emergency relief to markets, but it will not fully substitute for sustained cuts in Gulf output if the Strait of Hormuz remains closed for a long period.

Several Gulf producers have already reduced output after attacks on regional energy infrastructure, and Iran has warned it may further escalate by targeting power plants or fully blocking the strait if strikes on its infrastructure continue. That uncertainty is why governments activated strategic reserves and coordinated a rare, large release.

Bottom line: There is a global safety net of public and mandated industry oil stocks, led by China, the United States, Japan and major European holders. These reserves can calm markets and buy time, but they are not a long-term fix if major producers remain offline for an extended period.