U.S. refinery use reached its highest May–September level since 1998

U.S. refineries operated at unusually high rates between May and September 2026, with utilization averaging more than 95% of capacity, the highest for those months since 1998, the Energy Information Administration said on October 22. The agency linked the stronger operating pace to tight global supplies of refined products, particularly distillate fuel oil, which supported margins and export demand for U.S. diesel.

The seasonal comparison matters. EIA says U.S. utilization has averaged 92% from May to September since 1991, compared with 88% across the other seven months of the year. Refineries normally run harder before and during the summer driving season to supply gasoline. Because the same facilities also produce distillate fuels, the high summer runs generally build distillate inventories ahead of autumn maintenance and the winter heating and transport demand period.

Despite the highest seasonal utilization since 1998, total refinery output was only at its highest level since 2019. EIA attributes part of the difference to capacity: U.S. refining capacity has fallen 4% since 2019. The figures therefore describe a more intensively used, smaller fleet rather than a return to the earlier level of installed capacity. The agency also reported that utilization in the first three weeks of October eased from the summer peak but remained above the 2021–2025 seasonal average.

EIA based the analysis on its Weekly Petroleum Status Report. Utilization is refinery inputs measured against operable capacity, not a direct measure of finished fuel sales or exports. The release identifies tight distillate supply and stronger international demand as drivers, but it does not quantify the contribution of each factor to the utilization rate. The agency’s comparison is limited to the periods stated; it does not establish that high utilization will persist through the maintenance season or winter.

The utilization record needs to be read alongside the size of the refinery system. EIA says output was at its highest since 2019, while utilization for May–September was at its highest since 1998; the different benchmarks reflect the 4% reduction in capacity since 2019. Its weekly data show utilization easing from late-summer peaks during October’s first three weeks, though remaining above the 2021–25 seasonal average. The analysis does not forecast a winter continuation, and it does not break down the contribution of export demand, supply tightness or maintenance to each weekly movement.