Washington state is now reporting the highest average gas price in the United States, according to data current as of mid‑September 2025. Multiple recent reports confirm the current price for a gallon of regular unleaded gasoline in Washington is about $4.66, exceeding both the national average of approximately $3.20 and rivals such as California. The price surge is driven by three verified supply factors. First, the Olympic Pipeline, which carries refined fuel from Washington refineries to distribution terminals including Portland, was shut down around September 2 and has only recently resumed operations.
This outage reduced the flow of fuel into key regional hubs. Second, refineries in Washington and California have entered periods of planned and unplanned maintenance. These maintenance events have led to temporary reductions in refinery production capacity. Third, retailers have only recently been permitted to sell winter blend gasoline, which is cheaper to produce than summer blends. This seasonal transition began around September 15. Until that date, many gas stations were still distributing the more expensive summer blend.
Pipeline shutdown and refinery work affect fuel supply
State policy also contributes measurable cost components. As of July 1, 2025, Washington increased its state gas tax from 49.4 cents to 55.4 cents per gallon. State law now mandates that this tax rate will increase by 2 percent annually beginning in July of the following year. Washington’s fuel taxes are among the highest in the country. The state’s carbon emissions cost under the Climate Commitment Act also adds a regulatory cost component to gasoline. Geographic and infrastructural features of Washington and the broader Pacific Northwest region amplify the impact of supply disruptions.
The region has limited refining capacity: Washington has five refineries, primarily located near Tacoma and Seattle, while Oregon has none. Oregon depends significantly on fuel delivered via Washington’s pipeline and terminal systems. Recent weekly data shows Washington’s average gas price rose by 16.5 cents per gallon over a one‑week span, the largest such increase of any state in the country. In comparison, Oregon’s average jumped about 15 cents in the same period.
Carbon pricing law adds to pump price pressure
Within Washington, differences are apparent between counties. For example, a gallon of gas in King County averages $4.88, whereas in Spokane County it is about $4.31. Drivers and businesses in Washington are currently paying approximately $1.45 to $1.65 more per gallon than the national average. Washington’s rise to the top in gas prices reflects recent tax increases, infrastructure costs, regulatory fees, supply chain disruptions, and seasonal production changes. – By Content Syndication Services.