California Gas Prices Top $6 Again as Refinery Closures Meet a Volatile Oil Market
California drivers are paying more than $6 a gallon again. AAA reported on Sept. 18 that the statewide average for regular gasoline rose 19 cents in a week to $6.08, about $1.43 above the $4.66 average of a year ago. Diesel averaged $8.35, and San Francisco ($6.23) and Oakland ($6.13) topped the major metro averages, while Fresno ($6.05) and Sacramento ($6.01) sat just above the $6 line. The state average had slipped below $6 in early June, so this marks a return to spring-peak territory. AAA: California Gas Average Tops $6 a Gallon +2
The immediate driver is crude oil. AAA’s Doug Johnson said crude is averaging around $100 a barrel amid continued volatility in the Strait of Hormuz, and U.S. benchmark WTI settled at $102.43 on Wednesday after falling $3.40 that day. Nationally, regular gasoline averaged $4.43, up 16 cents on the week and more than $1 above last year, edging toward this year’s record of $4.56 set May 21. Gasoline demand rose to 8.79 million barrels a day last week, according to EIA data cited by AAA, even as U.S. crude inventories fell by 0.6 million barrels. AAA: California Gas Average Tops $6 a Gallon +2
California’s premium over the rest of the country also has a structural cause. UC Davis economists warned in 2025 that the shutdowns of Phillips 66’s Wilmington refinery and Valero’s Benicia refinery, which held 8.3% and 8.6% of state refining capacity, could lift California prices by $1.21 by August 2026 if nothing else changed, with about 40 cents of that arriving almost immediately after the first closure. That study predates this year’s oil-price spike, so the two pressures are now compounding. UC Davis College of Agricultural and Environmental Sciences
S&P Global reported in May that California has moved toward an import-dependent supply model for refined fuels at a time when other regions are also scrambling for supply. Los Angeles gasoline blendstock traded at a 47.7-cent premium to the New York futures benchmark as of May 20, up from a 27-cent average in the second quarter of 2025. The diesel premium widened even more, from 6.8 cents to 35 cents over the same comparison. S&P GlobalS&P Global
The path to $6 has been bumpy. In Contra Costa County, which AAA tracks in detail, the average climbed from $4.23 on Jan. 9 to $6.22 on May 8, then eased to about $5.45 by early July. It held between roughly $5.44 and $5.63 through late August before rising to $5.80 on Sept. 4 and $6.11 on Sept. 17. Contra Costa News
The gap with cheaper states is wide. Texas averages $3.83 and Indiana $3.56, so California drivers pay more than $2 a gallon above the Texas price. Public EV charging is also pricier in California, at 47 cents per kilowatt-hour compared with a 42-cent national average. At the statewide average, filling a 15-gallon tank costs about $91. Contra Costa NewsContra Costa News
What to watch: AAA publishes updated figures every week, and the direction will depend on crude prices and whether shipping conditions in the Strait of Hormuz stabilize. Contra Costa’s May peak of $6.22 is the next marker for a state average that is climbing again.
Sources: AAA weekly release via Contra Costa News (contracosta.news/2026/09/18/aaa-california-gas-average-tops-6-a-gallon/); UC Davis CAES (caes.ucdavis.edu/news/california-gas-prices-set-soar-2026); S&P Global (spglobal.com, May 22, 2026)