IFTA quarterly filings are due in 2026. Calculate your exact fuel tax liability across all 48 IFTA jurisdictions using current 2026 state tax rates.
Several states updated their diesel fuel tax rates for 2026. Key changes affecting high-volume routes include California (68.0 cents/gal), Pennsylvania (74.1 cents/gal), and Illinois (59.6 cents/gal) — all among the highest in the country. States with lower rates like Wyoming (23.0 cents/gal) and New Mexico (22.9 cents/gal) remain attractive for fuel-stop planning.
IFTA quarterly filing deadlines for 2026: Q1 due April 30, Q2 due July 31, Q3 due October 31, Q4 due January 31, 2027. Late filing penalties begin at $50 or 10% of the net tax due, whichever is greater.
IFTA calculates your fuel tax liability based on where you drove versus where you bought fuel. If you drove 30% of your miles in California but only bought 10% of your fuel there, you owe California taxes on the difference. The calculator handles this math automatically for all 48 jurisdictions.