US SPR Drops to Four-Decade Low as Commercial Inventory Draws Accelerate
The SPR fell to 331.2 million barrels in June, masking commercial stock draws of 53 million barrels over ten weeks that the headline year-to-date figures conceal.
ICE Brent crude front-month was at $83.90 a barrel as of Monday morning, August 10 (2026-08-10), down sharply from $102.75 at the close of Tuesday June 2 (2026-06-02) as partial resumption of Strait of Hormuz flows pulled prices back from their peak. The price retreat has dimmed the urgency visible in June's headlines. The inventory math underlying it has not improved at the same pace.2,3
The US Strategic Petroleum Reserve stood at 331.2 million barrels after the week ending June 19 (2026-06-19), according to EIA data — below the 2023 trough reached during the Biden administration's emergency release program and the lowest level in over four decades. In that single week, another 9.1 million barrels left the reserve.3
The SPR number exposes a gap between headline and underlying inventory data. US crude inventories were down only 2.1 million barrels year-to-date as of late June (2026-06-23), according to API data. That figure has allowed many market participants to treat the drawdown as manageable. But commercial crude stocks excluding the SPR shed 53 million barrels over the prior ten weeks, at an average pace exceeding 5 million barrels per week. SPR releases bridged the difference and kept the year-to-date figures looking orderly.3
The weekly draw pace has been uneven. Commercial crude inventories fell 8.33 million barrels in the week ending June 12 (2026-06-12), then decelerated to 765,000 barrels the following week. But that apparent relief coincided with the 9.1-million-barrel SPR draw, suggesting the stability in commercial stocks came from government stockpiles rather than an improved supply balance.3
US domestic production has provided only marginal offset. EIA data for the week ending June 12 (2026-06-12) showed output at 13.806 million bpd, up 375,000 bpd year-on-year but essentially unchanged from 13.799 million bpd the prior week. Incremental US production growth at that rate does not replace the volumes the SPR has been releasing.3
The reserve is now 394 million barrels below its maximum capacity, implying a physical ceiling of roughly 725 million barrels. At 331.2 million barrels, the usable buffer for further emergency releases is substantially thinner than it was entering the crisis. Refilling it while release rates remain elevated is arithmetically difficult.3
The IEA described the Hormuz disruption as the largest supply shut-in in history, with more than one billion barrels removed from global markets since the blockage began.1 In late May (2026-05-30), ExxonMobil senior vice president Neil Chapman warned that Brent could spike to $150 to $160 per barrel if inventory floors were breached, citing internal model projections.1 By the afternoon of Tuesday June 23 (2026-06-23), ICE Brent front-month had fallen to $77.10 as Hormuz flows began to resume, a retreat of more than $25 from the early June peak in roughly three weeks.3
Applying an exponential decay framework to the PADD2 and PADD3 draw rates against the SPR drawdown trajectory makes the ten-week pace of 53 million barrels in commercial draws harder to dismiss even as prices have eased. The year-to-date inventory figures present the US supply position as broadly stable, but they are a composite of two diverging trends: rising commercial draws and a reserve being released faster than it can be replenished.3
NYMEX WTI crude front-month was at $78.02 as of Monday morning (2026-08-10), up from $73.34 in the afternoon session of Tuesday June 23 (2026-06-23). The Hormuz partial recovery explains that bounce.3 The key variable in the coming weeks is the pace of SPR draws since the June 19 (2026-06-19) read — if releases continued anywhere near the 9.1-million-barrel weekly rate, the reserve has narrowed further since. Any renewed Hormuz disruption would find it thinner than at any point in the past four decades.3