The IFTA fuel tax is not a separate tax rate at all. It’s the mechanism the International Fuel Tax Agreement uses to let interstate motor carriers file a single quarterly return through their home jurisdiction and have that return redistribute fuel tax revenue to every state or province where the carrier actually burned fuel. Forty-eight U.S. states and 10 Canadian provinces participate. A carrier crossing a dozen states on one run reports all of that fuel consumption on one return, and the base jurisdiction handles the split.
Who Needs an IFTA License
IFTA applies to what the agreement calls a “qualified motor vehicle.” You need a license if your vehicle is used to transport people or property, operates in two or more IFTA member jurisdictions, and meets any of these size thresholds:
- Two axles with a gross vehicle weight or registered gross vehicle weight over 26,000 pounds
- Three or more axles, regardless of weight
- A combination of vehicles where the combined weight exceeds 26,000 pounds
If you meet one of those criteria and cross state lines, you either hold an IFTA license or buy trip permits for each entry into another jurisdiction.1IFTA, Inc. (International Fuel Tax Association). Carrier Information
Two categories of vehicles are exempt. Vehicles that never leave their home state don’t trigger IFTA, since the agreement only governs interstate and interprovincial travel. Recreational vehicles like motorhomes and pickup-camper rigs are exempt only when used exclusively for personal pleasure. The moment a recreational vehicle is tied to a business operation, that exemption disappears.1IFTA, Inc. (International Fuel Tax Association). Carrier Information
Not everywhere is covered. Alaska, Hawaii, the District of Columbia, the Northwest Territories, Nunavut, Yukon, and Mexico are not IFTA members. If you drive into any of them, your IFTA credentials do not authorize you there, and you’ll need to follow that jurisdiction’s own fuel tax rules.
How the Fuel Tax Is Calculated
Every jurisdiction sets its own fuel tax rate, and those rates change quarterly. The IFTA tax rate matrix on the IFTA, Inc. website lists current rates for every member jurisdiction and updates each quarter.2IFTA, Inc. International Fuel Tax Association. Tax Rates What IFTA does is reassign that revenue so each state receives tax proportional to the fuel actually consumed on its roads, not just the fuel purchased inside its borders.
The calculation runs in four steps.
- Calculate your fleet’s average fuel mileage. Divide total miles driven across all jurisdictions by total gallons of fuel consumed. Round to two decimal places.
- Determine taxable gallons per jurisdiction. Divide miles driven in each jurisdiction by that fleet average. The result is the gallons you’re treated as having consumed there.
- Subtract fuel already taxed. Compare taxable gallons for each jurisdiction against gallons actually purchased there. Bought more than you consumed? You have a credit. Consumed more than you bought? You owe the difference.
- Apply each jurisdiction’s tax rate to the net taxable gallons, positive or negative, to get the tax owed or credit for that state.
Adding the results across all jurisdictions produces one net balance: either a payment or a refund. The math rewards buying fuel in higher-tax states where you drive fewer miles, and penalizes the reverse. Most carriers end each quarter owing some states and getting credits from others, netted into one number.
A few states, including Indiana, Kentucky, and Virginia, add surcharges on top of their base rates. Surcharges are calculated the same way and appear as separate line items on your return.
Quarterly Filing Deadlines and Penalties
Returns are due four times a year, on the last day of the month following each quarter:
- First quarter (January–March): April 30
- Second quarter (April–June): July 31
- Third quarter (July–September): October 31
- Fourth quarter (October–December): January 31
When a due date falls on a weekend or legal holiday, the deadline moves to the next business day. You must file for every quarter in which you hold an IFTA license, even if your trucks didn’t move. Zero-activity returns are still required.
Filing late, failing to file, or underpaying triggers a penalty of $50 or 10 percent of the delinquent tax, whichever is greater. Interest accrues monthly on any unpaid balance starting the day after the due date. For U.S.-based carriers, the IFTA interest rate is set each January at two percentage points above the IRS underpayment rate. For 2026, that is 7 percent annually, or roughly 0.583 percent per month.3IFTA, Inc. International Fuel Tax Association. IFTA Annual Interest Rate Repeated missed filings or ignored balances can lead to license suspension or revocation, which effectively ends interstate operations.
Getting and Renewing Your License
You apply through your base jurisdiction, meaning the state or province where your qualified vehicles are registered, where you have some actual travel, and where your operational control and records live or can be produced.1IFTA, Inc. (International Fuel Tax Association). Carrier Information Most states handle applications online. You’ll typically provide your business name and address, your Federal Employer Identification Number, and vehicle details including VINs and plate numbers.
Once approved, the base jurisdiction sends an IFTA license and two decals for each qualified vehicle. A copy of the license goes in every qualified truck. The two decals go on the exterior of each vehicle, one on each side of the cab. Those credentials authorize operation in all 58 IFTA member jurisdictions.1IFTA, Inc. (International Fuel Tax Association). Carrier Information
Licenses and decals expire at the end of each calendar year. Renewal must be filed with your base jurisdiction before year end. Carriers who file renewal on time get a two-month grace period covering January and February, during which either the new year’s credentials or the prior year’s credentials are valid as long as the renewal application is in.4IFTA, Inc. 2026 Renewal Grace Period Miss the deadline and your trucks aren’t authorized to cross state lines under IFTA. A roadside stop without valid credentials can mean citations, forced trip permit purchases, or the vehicle being held.
Records You Have to Keep
IFTA record keeping splits into fuel and mileage, both broken down by jurisdiction, both detailed enough to survive an audit.
Every fuel purchase must be documented with the date, seller name and address, number of gallons, fuel type, price per gallon or total amount, and the specific vehicle that received the fuel. Bulk fuel withdrawals need the same detail.5iftach.org. Procedures Manual – Recordkeeping Fuel placed into anything other than a qualified motor vehicle does not count toward tax-paid credits, so mixing fleet fuel between IFTA-qualifying trucks and exempt vehicles without separate records is a fast way to lose credits at audit.
Mileage records must be trip-by-trip, with beginning and ending odometer readings, routes traveled, and miles driven in each jurisdiction. A GPS track showing 400 miles isn’t enough on its own; the records have to allocate those miles by state.
GPS and Vehicle Tracking Systems
A GPS-based system used for distance records must log a position reading at least every 10 minutes while the engine is running. Each reading needs the date and time, latitude and longitude to at least four decimal places, the odometer reading from the engine control module (or the dashboard odometer if there is no ECM reading available), and a vehicle identifier. Data must be exportable in a spreadsheet-compatible format such as CSV or Excel. Static PDFs or screenshots don’t qualify.
Having an Electronic Logging Device for hours-of-service compliance doesn’t automatically cover IFTA. No IFTA certification program exists for ELD vendors, so an ELD meeting FMCSA rules says nothing about whether it captures the data IFTA auditors need.
How Long to Keep Records
All fuel and mileage records must be kept for four years from the return’s due date or filing date, whichever is later.5iftach.org. Procedures Manual – Recordkeeping If your account is under a jeopardy assessment or waiver, that window extends. Every IFTA member jurisdiction is required to audit an average of 3 percent of its accounts each year, so any given carrier has a meaningful chance of selection over a multi-year window.6IFTA, Inc. Audit Manual When an audit finds discrepancies, the auditor assesses additional tax plus interest and potentially penalties, going back as far as the retention period allows.
Trip Permits as an Alternative
If your operation stays mostly inside one state and only occasionally crosses a line, trip permits may fit better than a full IFTA license. A trip permit covers a single vehicle for one entry into one jurisdiction and is valid for a limited number of days, typically 7 to 20 depending on the state. Fees generally fall in the $20 to $50 range per permit. A handful of out-of-state trips a year costs less this way and avoids the ongoing quarterly filing burden. Once interstate runs become regular, the per-trip costs and paperwork make IFTA licensing the practical choice.1IFTA, Inc. (International Fuel Tax Association). Carrier Information
Electric and Alternative-Fuel Vehicles
Electric trucks are not exempt. Starting January 1, 2024, electricity became a reportable fuel type under the agreement following the passage of IFTA Ballot 8-2022. A battery-electric vehicle that meets the qualified motor vehicle thresholds and crosses jurisdiction lines must report electricity consumed on the IFTA return the same way as diesel or gasoline.7International Fuel Tax Association, Inc. EV Policy Memorandum Compressed natural gas, liquefied natural gas, liquefied petroleum gas, and similar alternative fuels have been reportable under IFTA for longer. The practical challenge with electricity is metering kilowatt-hours by jurisdiction, which not every fleet has implemented.