What Is IFTA?
IFTA - the International Fuel Tax Agreement - is a cooperative agreement among 48 U.S. states and 10 Canadian provinces that simplifies fuel tax reporting for commercial motor carriers operating across multiple jurisdictions.
Before IFTA, carriers had to file separate fuel tax returns with every state they operated in. IFTA consolidates all of these into a single quarterly return filed with your base state. Your base state then distributes the appropriate amounts to all other member jurisdictions based on your reported mileage and fuel purchases.
The net result of your IFTA return can be either a refund (if you paid more fuel tax at the pump than you owed based on miles driven) or a tax due (if you drove more miles in high-tax states than reflected in your pump purchases).
Who Must Have an IFTA License?
You must obtain an IFTA license if you operate a qualified motor vehicle that travels in more than one IFTA member jurisdiction. A qualified motor vehicle is:
- A vehicle with 2 or more axles with a gross vehicle weight or registered weight exceeding 26,000 lbs, OR
- A vehicle with 3 or more axles regardless of weight
If your operations are entirely intrastate - you never cross a state line - you are not subject to IFTA. You would instead file under that state's intrastate fuel tax program.
IFTA Quarterly Due Dates (2026)
Missing an IFTA filing deadline results in penalties and interest. Mark these dates clearly in your compliance calendar every year:
| Quarter | Reporting Period | Filing Due Date |
|---|---|---|
| Q1 | January 1 – March 31 | April 30 |
| Q2 | April 1 – June 30 | July 31 |
| Q3 | July 1 – September 30 | October 31 |
| Q4 | October 1 – December 31 | January 31 |
If the due date falls on a weekend or holiday, the filing is typically due the next business day. Check with your base state for confirmation.
Records You Must Keep
IFTA requires you to keep detailed trip records for every qualified vehicle. These records must support the mileage and fuel purchase figures you report on your quarterly return:
Mileage Records (per trip, per vehicle):
- Beginning and ending odometer readings
- Miles traveled in each state or province
- Trip origin and destination
- Vehicle unit number
- Date of travel
Fuel Purchase Records:
- Date of each fuel purchase
- Fuel type and quantity (gallons)
- Location of purchase (city and state)
- Fuel vendor name
- Fuel receipt or invoice number
All IFTA records must be retained for 4 years from the filing due date of the return they support. IFTA audits can reach back up to 4 years, and missing records result in estimated assessments that are almost always unfavorable to the carrier.
How IFTA Calculates Your Tax
IFTA uses a straightforward calculation:
- Calculate your fleet's average fuel mileage - Total miles driven across all jurisdictions divided by total gallons consumed
- Determine fuel consumed per jurisdiction - Miles driven in each state divided by your average fuel mileage
- Apply each jurisdiction's tax rate - Each state has a different fuel tax rate per gallon
- Subtract taxes already paid - Fuel purchased in a state includes that state's tax at the pump
- Net result - The difference between taxes owed and taxes paid across all jurisdictions
Most IFTA software handles this calculation automatically. Manual calculation is possible but error-prone.
Common IFTA Mistakes and How to Avoid Them
Missing filing deadlines - The penalty for late filing is the greater of $50 or 10% of the net tax due, plus interest on any unpaid amounts. Set calendar reminders 2–3 weeks before each due date.
Not keeping fuel receipts - Bulk fuel purchases from your own tank must be documented with dispensing records. Credit card statements are not sufficient - you need itemized fuel receipts.
Reporting estimated rather than actual mileage - Odometer readings must support your reported per-jurisdiction mileage. GPS data is acceptable as a substitute for manual odometer logs.
Forgetting to report miles in states where no fuel was purchased - All miles driven in IFTA jurisdictions must be reported, even if you didn't buy fuel there. Failure to report these miles is considered tax evasion.
Using the wrong fuel type - Diesel and gasoline have separate IFTA calculations. If your fleet uses both, they must be tracked and reported separately.
Frequently Asked Questions
Does IFTA apply to intrastate carriers?
No. IFTA only applies to carriers operating qualified vehicles in more than one member jurisdiction. If you operate exclusively within one state, you are subject to that state's intrastate fuel tax program instead.
What is the penalty for a late IFTA filing?
Most member states charge a penalty of the greater of $50 or 10% of the net tax due, plus interest on any unpaid tax. Some states have higher minimum penalties. Filing on time - even if you can't pay immediately - reduces the total amount owed.
Can HaulComply help with IFTA compliance?
HaulComply tracks IFTA quarterly filing deadlines and sends reminders well in advance of each due date. It's part of the integrated regulatory filing calendar that covers IFTA, UCR, and other recurring compliance obligations.
What is an IFTA audit?
An IFTA audit is a review of your trip records, fuel receipts, and quarterly returns by your base state. Audits can be triggered by incomplete filings, inconsistencies in reported data, or random selection. The primary defense against an unfavorable audit outcome is complete, accurate records retained for the full 4-year window.
