West Coast (PADD 5) diesel price

No interstate pipeline connects the West Coast, EIA's PADD 5, to the rest of the country's refined-product network, so unlike the East Coast or Midwest it cannot lean on Gulf Coast supply when local production runs short. The district, which spans California, Oregon, Washington, Arizona, Nevada, Alaska and Hawaii, has to supply itself from in-region refineries, concentrated in California and around Puget Sound, and fill any gap with costlier waterborne cargoes. Because California sits inside this total, PADD 5 is consistently the highest of the five districts, by a wide margin.

An unplanned refinery outage anywhere on the coast tends to move this number more than a comparable outage would move a pipeline-connected region, since there is no backfill option. This total includes California, which has its own page. The chart also draws EIA's West Coast except California line, the same district with the state taken out, covered further down this page.

Calling PADD 5 an island is close to literal. Its refineries sit in two clusters, the California Bay Area and Los Angeles basin, and the Puget Sound corridor north of Seattle, and everything between and beyond them is served by pipeline out of those clusters or by ship. Arizona and Nevada have no refining of their own and take product by pipeline from California and from Texas; Alaska and Hawaii are separate supply islands inside the same reported district. What are PADDs covers how five districts drawn in 1942 ended up grouping places this different together.

When the coast runs short, resupply comes by sea, and that is expensive and slow. A cargo from Asia takes weeks; a domestic cargo from the Gulf has to move through the Panama Canal on a Jones Act vessel, of which there are few. The practical result is that a West Coast supply gap does not close the way an East Coast one does, and the price has to stay high long enough to attract the cargo. That is the structural reason PADD 5 sits at the top of the map rather than merely above average.

Fuel specifications add the rest. California requires CARB diesel, a tighter formulation than the federal standard that fewer refineries are set up to make, and the state's low-carbon fuel programs and excise taxes stack on top. Because California is the largest piece of this total, those state-level costs are visible in the district figure even though they apply in only one of its states, which is exactly why EIA publishes California and the rest of the district as separate figures.

How West Coast diesel compares with the US average

The gap is West Coast diesel minus the US average from the same EIA Monday survey, in cents per gallon, so a move elsewhere in the country shifts it even in a week the local price holds still.

For the week of Oct 5, 2026, West Coast diesel ran 103.0 cents a gallon over the US average ($7.229/gal against $6.199/gal), the second highest of the 10 regional breakouts that week. That is 24.8 cents above its 52-week median of +78.2 cents.

Over the past 52 weeks the gap has run from +63.7 cents (week of Mar 2, 2026) to +128.1 cents (week of Apr 6, 2026). Since EIA's June 2022 survey redesign, West Coast diesel has priced above the US average in every one of the 226 weekly surveys, and the gap has averaged +63.6 cents a gallon in December through February and +71.8 cents in June through August, so on average West Coast diesel has sat 8.2 cents lower against the US average in winter than in summer.

West Coast vs the Gulf Coast

Measured against the Gulf Coast (PADD 3) instead of the US average, this is the widest structural gap on the diesel map: the most expensive district against the one where most US diesel is made. A West Coast refinery outage widens it quickly, and a Gulf hurricane or turnaround narrows it from the other side.

For the week of Oct 5, 2026, West Coast diesel ran 141.0 cents a gallon over the Gulf Coast ($7.229/gal against $5.819/gal). That is 28.5 cents above its 52-week median of +112.5 cents.

Over the past 52 weeks the gap has run from +92.6 cents (week of Aug 24, 2026) to +155.1 cents (week of Apr 20, 2026). Since EIA's June 2022 survey redesign, West Coast diesel has priced above the Gulf Coast in every one of the 226 weekly surveys, and the gap has averaged +94.0 cents a gallon in December through February and +103.2 cents in June through August, so on average West Coast diesel has sat 9.3 cents lower against the Gulf Coast in winter than in summer.

The West Coast without California

EIA also publishes PADD 5 with California taken out: Oregon, Washington, Arizona, Nevada, Alaska and Hawaii, charted above as the West Coast except California line. The rollup exists so the rest of the West Coast can be read apart from California's own fuel specification and state taxes. It is still cut off from the interstate pipeline network, so the premium that remains is mostly the cost of isolation and freight. For the week of Oct 5, 2026, West Coast except California diesel ran 29.1 cents a gallon over the US average, and since EIA's June 2022 survey redesign it has priced above the US average in every one of the 226 weekly surveys.

The supply geography inside it is not one market. The Pacific Northwest runs on the Puget Sound refineries and the pipeline that carries their product south toward Portland. Arizona and Nevada have no refineries and take product by pipeline from California and from the Gulf Coast, so a California refinery problem can still reach this figure. Alaska and Hawaii are inside it too, supplied locally or by marine cargo, but they are small enough to move it very little.

The chart above starts in July 2021. Weekly West Coast prices go back to the week of Mar 21, 1994 on the diesel price history chart, which also tables every region's annual average and record high and low.