EIA Weekly On-Highway Diesel Survey - week of August 31, 2026
Diesel cost per gallon in California
EIA surveyed California at $7.218 per gallon for on-highway diesel in the week of August 31, 2026 (series EMD_EPD2D_PTE_SCA_DPG), $1.62 above the US average of $5.599.
Diesel tax breakdown
Tax rates: Federation of Tax Administrators state motor fuel table and state revenue departments. Not EIA data. The percentage is against the EIA figure shown above, which is a district figure unless California is surveyed directly.
Neighbouring states
Neighbours in the same EIA district carry the same published figure. A matching price here means the federal survey shows no measured gap across that border, not that pumps are identical.
What shapes the diesel price in California
California is the one state with its own EIA weekly on-highway diesel series, and it prices well above the contiguous US. Three structural reasons. CARB diesel specifications require additional refining steps and a separate supply chain from the rest of the country. California's combined state diesel tax is the highest in the lower 48 once cap-and-trade compliance cost is counted. And California's refinery capacity cannot meet in-state demand, so finished product arrives by tanker. California is also the only state in the contiguous US that cannot receive fuel by pipeline from Gulf Coast refineries, because no finished-product line crosses the Sierra Nevada.
The trip calculator starts at $7.22/gal, the EIA figure above. Change it to the price you actually see at the pump for a real answer.