IFTA Quarterly Fuel Tax Calculator Worksheet (Free)
The International Fuel Tax Agreement (IFTA) lets you file one quarterly fuel-tax return with your base jurisdiction instead of one with every state and province you drove through. The return is simple arithmetic — but it has to be done per jurisdiction, from records that will survive an audit. This worksheet walks the calculation step by step, gives you a fill-in table for each quarter, and lists the records you must be able to produce. Free printable Word version below — just tell us where to send it.
⬇ Download the IFTA calculator worksheet (Word)
Do you need an IFTA licence?
- You operate a qualified motor vehicle: two axles and a gross vehicle weight or registered weight over 26,000 lb; or three or more axles regardless of weight; or a combination over 26,000 lb.
- The vehicle travels in two or more IFTA member jurisdictions (the 48 contiguous U.S. states and 10 Canadian provinces).
- If you only occasionally leave your base state, compare the cost of trip permits against a licence — but a licence is usually simpler once you cross lines every month.
- Licence is issued by your base jurisdiction; two decals per qualified vehicle, renewed annually (new-year decals must generally be displayed by the end of February).
Quarterly due dates
| Quarter | Period covered | Return and payment due |
|---|---|---|
| Q1 | January – March | April 30 |
| Q2 | April – June | July 31 |
| Q3 | July – September | October 31 |
| Q4 | October – December | January 31 |
If the due date falls on a weekend or holiday, most jurisdictions accept the next business day — check yours. A return is due every quarter you hold a licence, even a quarter with zero travel (file a "no operations" return).
The calculation, step by step
- Total miles for the quarter, all qualified vehicles, all jurisdictions (including non-IFTA miles such as trip-permit or exempt miles, which are tracked separately but count in the MPG).
- Total gallons of fuel placed in the qualified vehicles during the quarter (from receipts, all jurisdictions).
- Fleet average MPG = total miles ÷ total gallons. Round per your jurisdiction's instructions (commonly two decimal places).
- For each jurisdiction: taxable miles driven there ÷ fleet MPG = taxable gallons consumed there.
- For each jurisdiction: taxable gallons − tax-paid gallons purchased there = net taxable gallons (negative means you over-purchased there and earn a credit).
- Net taxable gallons × that jurisdiction's current quarter tax rate (published on iftach.org each quarter; rates change) = tax due or credit.
- Sum every jurisdiction's tax due / credit. Credits offset amounts owed elsewhere; the net is what you pay your base jurisdiction (or receive as refund/credit).
- Add any surcharge lines — a few jurisdictions levy a surcharge on taxable gallons that is not offset by tax-paid purchases.
Per-jurisdiction worksheet (one row per state/province driven)
| Jurisdiction | Total miles | Taxable miles | Taxable gal (miles ÷ MPG) | Tax-paid gal bought | Net gal | Rate | Tax due / (credit) |
|---|---|---|---|---|---|---|---|
| Totals |
Fleet summary for the quarter
| Quarter / year | |
| Total miles (all jurisdictions) | |
| Total gallons purchased | |
| Fleet MPG (miles ÷ gallons) | |
| Sum of tax due | |
| Sum of credits | |
| Net payable / (refund) |
Records an auditor will ask for (keep four years)
IFTA requires distance and fuel records to be kept for four years from the return due date or filing date, whichever is later.
- Trip records for every trip: date, origin and destination, route, beginning and ending odometer or hubodometer, total trip miles, miles by jurisdiction, vehicle unit number, driver.
- ELD/GPS distance data is accepted by most jurisdictions if it captures location at regular intervals and can produce jurisdiction totals — confirm your system's IFTA report meets your base state's requirements.
- Fuel receipts showing date, seller name and address, fuel type, gallons, price, vehicle unit number and purchaser name. Bulk fuel needs withdrawal logs by vehicle.
- A summary by quarter reconciling trip miles to odometer readings — gaps between trips are a classic audit finding.
- Copies of each filed return and payment confirmation.
Never let a deadline take a truck off the road
Enter your dates once — FleetClear computes every DOT/FMCSA deadline, alerts you at 60/30/7 days, and drafts the renewal notice. Your first compliance item is free.
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