The US Strategic Petroleum Reserve (SPR) has fallen to its lowest level since 1983 after more than 110 million barrels were withdrawn since late March as part of an emergency response to global oil supply disruptions following US and Israeli strikes on Iran.
According to data compiled by Anadolu from the US Energy Information Administration (EIA), the SPR stood at around 304.8 million barrels in the week ending July 31.
Based on the EIA’s weekly data series, which dates back to August 1982, the reserve fell to its lowest level since the week ending Feb. 25, 1983, when it stood at about 305.3 million barrels.
The decline follows the emergency release of oil after US and Israeli strikes against Iran on Feb. 28 disrupted crude oil and petroleum product flows through the Strait of Hormuz, affecting roughly 20 million barrels per day of global oil supplies.
Although pipeline infrastructure across the Gulf partially offset the disruption, the interruption created a significant supply shortfall in global markets.
In response, the International Energy Agency (IEA) launched the largest coordinated emergency oil stock release in its history, announcing that member countries would collectively make 400 million barrels of oil available to the market.
As part of the coordinated effort, the US Department of Energy announced on March 11 that 172 million barrels of crude oil would be released from the SPR over approximately 120 days.
If the remaining barrels under the emergency release program are withdrawn, the SPR could fall to around 243 million barrels, leaving the US with roughly 59% of the reserve it held at the start of the year.
Although the EIA does not specify a minimum level required for energy security, the sharp reduction would materially reduce the volume of crude available for a future emergency drawdown.
– More than 110 million barrels withdrawn since late March
EIA data showed that the first decline in the SPR following the emergency release announcement was recorded in the week ending March 27.
The reserve fell from around 415.4 million barrels in the week ending March 20 to about 304.8 million barrels by the week ending July 31, meaning approximately 110.6 million barrels have been withdrawn since late March.
The data also indicate that the volume announced under the 172-million-barrel SPR release program has not yet been fully supplied to the market.
EIA data show that the SPR ended 2025 at around 413.5 million barrels.
The reserve reached its all-time high of about 726.6 million barrels in early 2010.
Established in the aftermath of the oil crises of the 1970s, the SPR is stored at four sites along the US Gulf Coast and is intended to help cushion the impact of unexpected disruptions to oil supplies.
