IFTA
Also called International Fuel Tax Agreement
IFTA is an agreement among US states and Canadian provinces that lets an interstate carrier file one quarterly fuel tax return, redistributing fuel tax to the jurisdictions where miles were actually driven.
Last reviewed · by the Fleetchart team
Before IFTA a carrier needed a permit and a filing for every state entered. Under IFTA the carrier licenses in its base jurisdiction and files a single quarterly return.
The return reconciles two things: miles driven in each jurisdiction, and fuel purchased in each jurisdiction. Where you bought fuel and where you burned it rarely match, so the filing produces a payment or a credit.
The practical requirement is record-keeping: mileage by jurisdiction and every fuel receipt. Missing receipts do not reduce what you owe — they only remove the credit you would have received.
Who needs it: carriers running qualified motor vehicles in more than one member jurisdiction. Under the IFTA Articles of Agreement, that means a vehicle with two axles and over 26,000 pounds, or three or more axles at any weight, or a combination over 26,000 pounds. Your base jurisdiction is where the trucks are registered, where you keep your records and where the fleet runs some miles.
The math works like this. Fleet MPG for the quarter = total miles ÷ total gallons. For each state, miles ÷ fleet MPG gives the taxable gallons. Subtract the tax-paid gallons you bought there to get net gallons, then multiply by that state's rate. Rates change each quarter and are published on the IFTA tax rate matrix at iftach.org.
Returns are due on the last day of the month after each quarter: April 30, July 31, October 31 and January 31. You must file even for a quarter with no miles. Keep your mileage and fuel records for four years from the due date or filing date, whichever is later.
Worked example
Three states in one quarter
A truck runs 10,000 miles and buys 1,600 gallons. Rates are the 4Q 2026 special diesel rates from the IFTA matrix, for illustration only.
| State | Miles | Taxable gal | Tax-paid gal | Net gal | Rate | Tax |
|---|---|---|---|---|---|---|
| Texas | 6,000 | 960 | 1,100 | −140 | $0.2000 | −$28.00 |
| Tennessee | 2,500 | 400 | 300 | 100 | $0.2700 | $27.00 |
| Georgia | 1,500 | 240 | 200 | 40 | $0.3730 | $14.92 |
- Fleet MPG: 10,000 ÷ 1,600 = 6.25.
- Taxable gallons: each state's miles ÷ 6.25.
- Net gallons: taxable − tax-paid. A negative number is a credit.
- Tax: net gallons × rate, then add the states together.
The return nets to $13.92 due. Fuel bought in Texas earned a credit that paid most of what was owed to Tennessee and Georgia.
Sources
- IFTA, Inc., Articles of Agreement (revised August 2026) · Definitions of base jurisdiction (R212) and qualified motor vehicle (R245), quarterly reporting (R930), the due date (R960) and tax-paid credits (R1010). (checked )
- IFTA, Inc., Procedures Manual (revised August 2026) · What a return reports per jurisdiction (P710, P720), fleet MPG to two decimal places, and the four-year record retention rule. (checked )
- IFTA, Inc., IFTA Tax Rate Matrix · Current quarterly fuel tax rates for every IFTA jurisdiction, including the 4Q 2026 special diesel rates quoted here. (checked )