What Gas Costs
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An independent guide to the price at the pumpData release · 11 September 2026

Taxes explained

Washington fuel taxes

Fixed duties and percentage taxes work differently. These records preserve effective dates and unresolved checks.

Amounts are in local currency per litre. Percentage entries are recomputed from each observed price. Snapshot dates are identified in the notes.
Tax / fuelRateEffective fromThroughStatus and source
Excise Fixed
gasoline
USD 0.2076/L2026-07-01Open / check sourceSource verified
Oil Spill Administration Tax: $0.0400/bbl ($0.0009523/gal). Oil Spill Response tax: $0.0100/bbl ($0.000238/gal). Hazardous Substance tax on petroleum products that can be measured on per-barrel basis: $1.4900/bbl ($0.0355/gal). "Border Zone Area Motor Fuel Tax" $0.01/gal in counties bordering Canada. Petroleum Products Tax (PPT) reinstated as of 1/1/20: rate is based on the wholesale value of the petroleum product multiplied by .0030. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included.
Excise Fixed
diesel
USD 0.2313/L2026-07-01Open / check sourceSource verified
Oil Spill Administration Tax: $0.0400/bbl ($0.0009523/gal). Oil Spill Response tax: $0.0100/bbl ($0.000238/gal). Hazardous Substance tax on petroleum products that can be measured on per-barrel basis: $1.4900/bbl ($0.0355/gal). "Border Zone Area Motor Fuel Tax" $0.01/gal in counties bordering Canada. Petroleum Products Tax (PPT) reinstated as of 1/1/20: rate is based on the wholesale value of the petroleum product multiplied by .0030. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included.
Excise Fixed
gasoline
USD 0.2046/L2026-01-01Open / check sourceSource verified
Oil Spill Administration Tax: $0.0400/bbl ($0.0009524/gal). Oil Spill Response tax: $0.0100/bbl ($0.000238/gal). Hazardous Substance tax on petroleum products that can be measured on per-barrel basis: $1.4800/bbl ($0.03524/gal). "Border Zone Area Motor Fuel Tax" $0.01/gal in counties bordering Canada. Petroleum Products Tax (PPT) reinstated as of 1/1/20: rate is based on the wholesale value of the petroleum product multiplied by .0030. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included.
Excise Fixed
diesel
USD 0.2284/L2026-01-01Open / check sourceSource verified
Oil Spill Administration Tax: $0.0400/bbl ($0.0009524/gal). Oil Spill Response tax: $0.0100/bbl ($0.000238/gal). Hazardous Substance tax on petroleum products that can be measured on per-barrel basis: $1.4800/bbl ($0.03524/gal). "Border Zone Area Motor Fuel Tax" $0.01/gal in counties bordering Canada. Petroleum Products Tax (PPT) reinstated as of 1/1/20: rate is based on the wholesale value of the petroleum product multiplied by .0030. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included.
Excise Fixed
gasoline
USD 0.2046/L2025-07-01Open / check sourceSource verified
Oil Spill Administration Tax: $0.0400/bbl ($0.0009524/gal). Oil Spill Response tax: $0.0100/bbl ($0.000238/gal). Hazardous Substance tax on petroleum products that can be measured on per-barrel basis: $1.4800/bbl ($0.03524/gal). "Border Zone Area Motor Fuel Tax" $0.01/gal in counties bordering Canada. Petroleum Products Tax (PPT) reinstated as of 1/1/20: rate is based on the wholesale value of the petroleum product multiplied by .0030. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included.
Excise Fixed
diesel
USD 0.2284/L2025-07-01Open / check sourceSource verified
Oil Spill Administration Tax: $0.0400/bbl ($0.0009524/gal). Oil Spill Response tax: $0.0100/bbl ($0.000238/gal). Hazardous Substance tax on petroleum products that can be measured on per-barrel basis: $1.4800/bbl ($0.03524/gal). "Border Zone Area Motor Fuel Tax" $0.01/gal in counties bordering Canada. Petroleum Products Tax (PPT) reinstated as of 1/1/20: rate is based on the wholesale value of the petroleum product multiplied by .0030. Rate observed at the EIA reporting snapshot; verify legislative effective date. Federal tax included.

Return to Washington prices · Read the explanation

Common questions

Does a percentage tax stay fixed in cents per litre?

No. VAT, GST and sales taxes vary with their taxable base. For a tax-inclusive price and one rate r, the tax amount is price × r / (1 + r).

Why are some tax records marked unverified?

A published summary can omit a local levy, a tax-base rule or an effective date. Unverified records are not treated as a complete statutory tax stack.