2025 IFTA tax rates by state: complete map with surcharge flags and Q4 updates

IFTA diesel rates in 2025 range from $0.19/gallon in Oklahoma to $0.74/gallon in Pennsylvania, but Indiana's effective rate hits $1.22/gallon when you include its surcharge—a trap that costs owner-operators hundreds per quarter if they don't account for it on the worksheet.

Indiana's $1.22 effective rate is the highest in the country; Pennsylvania's $0.74 is second

Indiana's $0.61/gallon base diesel rate combines with its surcharge formula to hit $1.22/gallon effective through Q3 2025. The state consolidates this into a $0.63/gallon all-in rate starting Q2 2026. Pennsylvania's Q3 2025 diesel rate of $0.74/gallon is second highest, with no additional surcharge.

The Indiana surcharge is calculated on total gallons consumed, not net taxable gallons, and it never generates a credit on your IFTA return. A driver who runs 800 gallons through Indiana in a single quarter owes $976 in tax ($0.61 base + $0.61 surcharge × 800), not the $488 they'd calculate by reading only the base rate.

IFTA Inc. publishes the authoritative member jurisdiction rates at iftach.org/taxmatrix4/, with each state responsible for its own accuracy. Indiana's motor-carrier fuel-tax page confirms the Q1–Q3 2025 rates and the Q2 2026 consolidation.

Four states layer hidden surcharges on top of base rates; Kentucky and Virginia are the most expensive trap states

Kentucky adds 10.5¢/gallon and Virginia adds 14.3¢/gallon on top of their base diesel rates. New York adds 0.95¢/gallon, and New Mexico adds 1.0¢/gallon. These surcharges are not tax-paid credits; you owe them even if you purchased more fuel than you consumed in that state.

Kentucky's base diesel rate for Q3 2025 is $0.245/gallon; the surcharge makes the total $0.350/gallon. Virginia's base is $0.244/gallon; add the 14.3¢ surcharge and you hit $0.387/gallon. Most owner-operators miss surcharge states because they only track the base IFTA rate and skip the surcharge line item on worksheets. Kentucky and Virginia rates fluctuate quarterly because their surcharges tie to fuel-price formulas, so you can't assume last quarter's rate holds.

Oklahoma, Mississippi, and Texas offer the cheapest fueling points; Oklahoma Q3 2025 rates are $0.19/gallon for diesel and $0.05/gallon for LNG

Oklahoma is the lowest-cost entry point for conventional fueling at $0.19/gallon diesel. Mississippi sits at $0.18/gallon and Texas at $0.20/gallon. Strategic fueling in low-tax states reduces your overall quarterly tax liability by 5–12%, depending on your route mix.

If you run alternative fuels, Oklahoma's rates collapse further. LNG and CNG both tax at $0.05/gallon in Oklahoma (Q3 2025). An LNG fleet that fuels 800 gallons in Oklahoma versus Pennsylvania saves $552 in tax on that fill-up alone ($0.74 − $0.05 × 800). Propane in Oklahoma is $0.16/gallon, still half what you'd pay in most high-tax states.

Worked example: Q3 2025 route through three states shows how base rates and surcharges compound

An owner-operator runs 5,800 miles in Q3 2025: 1,600 miles in Kentucky, 1,800 miles in Tennessee, and 2,400 miles in Ohio. Over the quarter, they purchase 862 gallons total: 280 gallons in Kentucky, 290 in Tennessee, and 292 in Ohio.

The Kentucky surcharge alone adds $29.40 to the tax bill, even though Kentucky's base rate of $0.245 looks reasonable on paper. A driver who only tracked base rates and skipped the surcharge would file short by nearly 10% and face an audit adjustment. Tennessee has no surcharge and the lowest total effective rate in this route. Ohio's $0.47 diesel rate is the highest but carries no surcharge.

Q4 2025 rate changes: Connecticut effective July 1, 2025; Indiana consolidated Q2 2026; Ohio CNG continues six-year climb

Connecticut's diesel fuel tax increased effective July 1, 2025. Indiana's surcharge folds into the base rate effective Q2 2026, bringing the consolidated rate to $0.63/gallon all-in—the first simplification of Indiana's surcharge system in a decade.

Ohio's CNG rate has climbed steadily: $0.10 in 2019, $0.20 in 2020, $0.30 in 2021, $0.40 in 2022, and $0.47 as of Q3 2025. A CNG carrier that fueled 1,000 gallons in Ohio in 2019 paid $100 in tax; that same fill-up costs $470 today.

Always use the rates in effect during the quarter you're filing for, not current quarter rates. If you file Q3 2025 in October, use Q3 rates, not Q4 rates. Mismatching quarters triggers audits.

Canadian provinces tax by liter, not gallon; do not convert to gallons on your IFTA return

Do not convert Canadian liter rates to gallons on your IFTA return. Report Canadian data in liters as-is. Cross-border carriers often fail a fuel-tax audit because they converted a Canadian province's liter rate to a gallon equivalent and reported it wrong. If you purchase 500 liters in Quebec, you report 500 liters on your return, not 132 gallons.

Q4 2025 Canadian rates: Alberta $0.3567/L diesel; British Columbia $0.4115/L; Saskatchewan $0.5542/L diesel; Quebec $0.5640/L diesel. Ontario is lowest at $0.2469/L for all fuel types; Newfoundland follows at $0.2606/L diesel.

IFTA rates change every quarter; verify rates directly from state motor-fuel-tax pages before filing

IFTA Inc. publishes the authoritative rate table at iftach.org/taxmatrix4/ before each quarter begins. Indiana, Kentucky, and Virginia rates fluctuate most often because they tie to fuel-price formulas. You can't assume last quarter's rate will hold.

Each state is solely responsible for its own rate accuracy; IFTA Inc. does not independently verify what member jurisdictions report. If a state publishes a wrong rate and you file based on it, you're still liable for the correct amount. Verify rates directly from state motor-fuel-tax pages or the official IFTA matrix before filing.