To fill out and file an IFTA report, you pull together your quarterly distance and fuel records, calculate your fleet’s average miles per gallon, work out how many gallons you consumed versus purchased in each jurisdiction, apply that jurisdiction’s current fuel tax rate to the difference, and submit the completed return to your base jurisdiction by the quarterly deadline. The return redistributes fuel tax so each state or province you drove through receives tax on the miles you actually traveled there.1IFTA, Inc. Carrier Information
One rule catches new filers off guard: once your IFTA license is active, a return is due every quarter, even if your trucks never crossed a state line or never rolled at all. A zero-mile return still has to be filed.
What You Need Before You Start Filling Out the Return
The return is only as accurate as the records behind it, and every number on the form traces back to two piles of paper (or their electronic equivalents): distance records and fuel records.
Individual Vehicle Distance Records
Each power unit needs an Individual Vehicle Distance Record (IVDR) for every trip. The IFTA Best Practices Audit Guide requires each IVDR to capture:
- Trip starting and ending dates
- Origin and destination (location codes are acceptable)
- Route of travel, or GPS latitude/longitude positions with the nearest town or intersection identified
- Beginning and ending odometer readings for the trip
- Total trip distance
- Distance driven in each jurisdiction
- Power unit number or vehicle identification number
- Fleet number and company name
Your base jurisdiction may also require the driver’s name and intermediate stops.2IFTA, Inc. Best Practices Audit Guide
Fuel Purchase and Bulk Withdrawal Records
Keep every receipt. Each one should show the date, vendor name, number of gallons, fuel type, and the unit that received the fuel. If you run your own bulk tanks, you also need a withdrawal log at every location, and every withdrawal has to be recorded (including fuel dispensed into non-IFTA equipment). Each entry should list the date, quantity and type of fuel, tank location, and the vehicle fueled.3Iowa Department of Transportation. IFTA Record Keeping Requirements
ELD and GPS Data
If you rely on an ELD or GPS system for distance, the data has to be detailed enough to validate total distance by jurisdiction. That means GPS readings frequent enough to identify jurisdiction crossings, beginning and ending odometer readings, calculated distance between readings, and per-unit distance broken out by jurisdiction. Electronic data is held to the same retention period as paper.
How to Calculate What Goes on the Return
The math is the same every quarter. Three steps:
- Divide total fleet miles by total gallons consumed to get your fleet average MPG for the quarter.
- For each jurisdiction, divide miles driven there by the fleet MPG to get gallons deemed consumed. Subtract the tax-paid gallons you purchased in that jurisdiction. A positive number is taxable; a negative number is a credit.
- Multiply the net gallons (owed or credit) by that jurisdiction’s fuel tax rate for the quarter.
Worked Example
Say a single truck ran 10,000 miles in Q2 2026 and burned 2,000 gallons of diesel. Fleet MPG is 10,000 ÷ 2,000 = 5.0. The truck logged 3,000 miles in Ohio, 4,000 in Indiana, and 3,000 in Illinois.
Gallons consumed in each jurisdiction:
- Ohio: 3,000 ÷ 5.0 = 600 gallons
- Indiana: 4,000 ÷ 5.0 = 800 gallons
- Illinois: 3,000 ÷ 5.0 = 600 gallons
Now subtract tax-paid gallons purchased in each state. Assume 500 gallons in Ohio, 1,000 in Indiana, and 500 in Illinois:
- Ohio: 600 − 500 = 100 net taxable gallons
- Indiana: 800 − 1,000 = −200 gallons (credit)
- Illinois: 600 − 500 = 100 net taxable gallons
Apply the Q2 2026 diesel rates:4IFTA, Inc. 3rd Quarter 2026 Fuel Tax Rates
- Ohio: 100 × $0.4700 = $47.00 owed
- Indiana: 200 × $0.6100 = $122.00 credit
- Illinois: 100 × $0.7380 = $73.80 owed
Net: $47.00 + $73.80 − $122.00 = −$1.20, a $1.20 credit. Credits can be applied to future quarters or refunded, depending on the base jurisdiction’s rules and the amount.
Handling Surcharges and Exempt Miles
Two adjustments change what lands on the IFTA-101 schedule.
Indiana, Kentucky, and Virginia impose a fuel tax surcharge on top of the base IFTA rate, and each surcharge is reported on its own line of the schedule.4IFTA, Inc. 3rd Quarter 2026 Fuel Tax Rates The surcharge follows the same consumed-minus-purchased logic, just multiplied by the surcharge rate instead of the base rate. Current surcharge rates are published alongside the base rates on the IFTA tax rate matrix each quarter.
Certain miles can also come off the taxable column. Off-highway routes, forest roads closed to the public, private roads, and some federal property qualify as exempt distance, and miles run under a jurisdiction trip permit are exempt from that jurisdiction’s taxable distance because the trip permit already covered the tax.5IFTA, Inc. Distance Exemptions Exempt miles still go into your total miles for the MPG calculation, but they get reported in the non-taxable column rather than the taxable one. Each jurisdiction publishes its own recognized exemptions, so confirm the category applies before claiming it. Carriers who lump exempt miles in with taxable highway miles pay tax they don’t owe.
When to File and What Late Filing Costs
Returns are due on the last day of the month following the close of each quarter. When that date falls on a weekend or holiday, the deadline shifts to the next business day. The 2026 dates:
- Q1 (January–March): April 30, 2026
- Q2 (April–June): July 31, 2026
- Q3 (July–September): November 2, 2026 (October 31 is a Saturday)
- Q4 (October–December): February 1, 2027 (January 31 is a Sunday)
Miss a deadline by a day and the penalty is $50 or 10 percent of the delinquent tax, whichever is greater. The same penalty applies to underpayment.6IFTA, Inc. IFTA Articles of Agreement – R1220 Interest accrues monthly at one-twelfth of the annual rate. For 2026, the IFTA annual interest rate is 9 percent, or 0.75 percent per month on any unpaid balance. That rate is set each January at two percentage points above the IRS underpayment rate.
Records to Keep After You File
Hold onto all fuel and distance records for at least four years from the date the return was due or filed, whichever is later.3Iowa Department of Transportation. IFTA Record Keeping Requirements That covers IVDRs, fuel receipts, bulk withdrawal logs, and GPS or ELD data. If you request a refund, the retention clock extends until the refund is processed or denied.7IFTA, Inc. IFTA Articles of Agreement – R1140
Auditors don’t just read the return. They pull samples of your IVDRs, trace them back to monthly and quarterly recaps, verify the equipment list, test recorded distance and fuel against original trip records, and check odometer readings for consistency. Errors found in a sample get projected across the full audit period.2IFTA, Inc. Best Practices Audit Guide Most audit assessments trace back to missing IVDRs, gaps in fuel receipts, or odometer readings that don’t reconcile across trips, rather than to any deliberate underreporting. Records that hold together on their own are what keep a return defensible years after you file it.