Washington IFTA Fuel Tax Rate
Washington's IFTA diesel rate for the 3rd quarter of 2026 is $0.5950 per gallon, up $0.0110 from Q2 2026.
Washington rate for Q3 2026
Special diesel, Q3 2026
$0.5950
per US gallon, up $0.0110 from Q2 2026
- Diesel tax rate
- $0.5950/gal
- Surcharge
- None listed
- Quarter
- Q3 2026, from Jul 1, 2026
- Change vs last quarter
- up $0.0110
Notes from the source
Matrix footnote #10 (WASHINGTON): Bio Diesel is reported as a Special Fuel at $0.595 a gallon and would be reported in the Diesel column.
Worked example: the Washington line of your IFTA return
Change the numbers to match your quarter. Prefilled with 10,000 total miles on 1,550 gallons, 1,200 of those miles in Washington, and 100 gallons bought there.
Washington vs. its neighbors, Q3 2026
| Jurisdiction | Diesel + surcharge | vs. WA |
|---|---|---|
| Washington | $0.5950 | — |
| British Columbia | $0.4060 | −$0.1890 |
| Idaho | $0.3200 | −$0.2750 |
| Oregon | $0.0000 | −$0.5950 |
On an IFTA return, a higher rate doesn't mean you pay more overall. Fuel you buy in a high-rate state earns a bigger credit. What matters is where you burn the fuel versus where you buy it.
Washington rate, last 4 quarters
Source: IFTA, Inc. Fuel Tax Rate Matrix, 3rd Quarter 2026 · Effective Jul 1, 2026 · Last verified Sep 28, 2026
IFTA, Inc. publishes the rates each member jurisdiction reports. Washington's tax agency is the final word on its rate.
Estimates for planning. Confirm with your tax pro or your base jurisdiction's IFTA office before filing.