US operable atmospheric distillation capacity, the primary measure of refinery capacity, totaled 18.2 million bbl/calendar day (b/cd) as of Jan. 1, 2026, down by more than 250,000 b/cd (about 1%) from a year earlier, according to the US Energy Information Administration (EIA)’s latest annual Refinery Capacity Report.

EIA reports refinery capacity in both b/cd and bbl/stream day (b/sd). Calendar day capacity reflects estimated input under typical operating conditions, accounting for maintenance and downtime, while stream day capacity represents maximum throughput under optimal conditions without downtime and is typically about 6% higher.

The 2026 report includes 130 operable refineries, two fewer than in 2025, following the closure of LyondellBasell’s 263,776-b/cd Houston refinery in March 2025 and Phillips 66’s 138,700-b/cd Los Angeles refinery in October 2025. Combined, the shutdowns reduced total US operable capacity by about 400,000 b/d, partially offset by incremental increases at other facilities.

The Los Angeles refinery closure represents a roughly 5% reduction in US West Coast (USWC; PADD 5) capacity. Limited pipeline connectivity from the US Gulf Coast (USGC) to the USWC increases the potential for regional supply impacts from such losses. Although Valero’s 145,000-b/d Benicia refinery remained operational as of Jan. 1, 2026, it has since ceased refining operations, and its capacity was removed from monthly estimates beginning in March.

On the USGC (PADD 3), the closure of the LyondellBasell refinery reduced regional capacity by about 3%. However, modest capacity additions at other USGC refineries limited the overall regional decline to less than 2% in 2025.

Among leading operators, Marathon, Valero, and ExxonMobil each reported calendar day capacity increases of less than 1% compared with 2025, reflecting incremental process improvements rather than major expansions. Phillips 66 reported a net capacity decline due to the Los Angeles closure. Chevron moved ahead of PBF Energy to become the fifth-largest US refiner following marginal capacity gains.

Motiva’s Port Arthur refinery remains the largest US refinery on a calendar day basis at 656,000 b/cd, while Marathon’s Galveston Bay refinery continues to rank as the largest on a stream-day basis at 678,000 b/sd.