Under the International Fuel Tax Agreement, IFTA mileage exemptions let you subtract specific categories of distance from your taxable total, most often miles driven off public roads, certain toll or turnpike miles, and miles already covered by a temporary trip permit. The catch is that each member jurisdiction decides on its own which categories it honors, so a mile that’s exempt in one place is fully taxable the moment you cross a border. You still report every mile the truck runs; the exempt portion just goes in a separate column on the return.
The Exemption Categories That Actually Exist
IFTA doesn’t have one master list of exempt miles that applies everywhere. The International Fuel Tax Association publishes a jurisdiction-by-jurisdiction exemptions matrix, and most jurisdictions recognize only a subset of the categories below.1International Fuel Tax Association. IFTA Distance Exemptions
Off-Highway and Private-Property Miles
This is the most commonly recognized category. Miles driven on roads not maintained with public funds — private ranch roads, logging paths, industrial job sites, and similar terrain where the vehicle never touches a publicly funded roadway — can be reported as nontaxable in jurisdictions that recognize the exemption. Fuel taxes fund public road infrastructure, and miles that don’t use public roads sit outside that logic.
Details vary and trip carriers up. Some jurisdictions require the off-road segment to exceed a minimum continuous distance before it qualifies. Others exclude private roads that are accessible to the general public, even if the road is privately owned. Federal property open to general traffic typically doesn’t qualify either. The exempt miles still appear in your total distance; they just move to the exempt column.
Turnpike and Toll Road Miles
A small number of jurisdictions treat turnpike or toll road miles as nontaxable, on the theory that toll revenue already funds those roads. As of 2026, only a handful of jurisdictions offer this exemption.1International Fuel Tax Association. IFTA Distance Exemptions The same stretch of toll highway is taxable in the vast majority of places. If you claim it where it’s allowed, plan to keep every toll receipt and fuel invoice as backup.
Trip Permit Miles
If a carrier operates a qualified motor vehicle through a jurisdiction without an IFTA license, a temporary trip permit covers the fuel tax for that trip. Miles run under a trip permit are included in total reported distance but are typically exempt from taxable miles on the IFTA return, because the tax was already paid at the permit purchase.
A Boundary: PTO Fuel Is Not a Mileage Exemption
Fuel burned while the truck is stationary — running a refrigeration unit, a hydraulic pump, or other power take-off equipment — is not handled through a mileage exemption. The IRS treats PTO fuel separately: you determine a reasonable estimate of the fuel used for nonpropulsion purposes and exclude it from the fuel tax, supported by adequate records of your operating experience.2Internal Revenue Service. Publication 510, Excise Taxes There’s no fixed percentage or formula, and it doesn’t belong in your exempt-miles column.
Why the Jurisdiction Matters More Than the Category
Each IFTA member jurisdiction picks which exemption categories to honor. One might exempt off-highway miles, forest roads, and turnpike travel. A neighbor might recognize no distance exemptions at all. The exemptions list also changes: jurisdictions add and remove categories from year to year.1International Fuel Tax Association. IFTA Distance Exemptions
You can’t apply one jurisdiction’s rules across a whole route. A carrier crossing three jurisdictions might have exempt off-highway miles in the first, no exemptions in the second, and a turnpike exemption in the third. Each jurisdiction’s slice of the trip gets its own treatment. Claiming an exemption in a jurisdiction that doesn’t recognize it gets flagged in audit and produces back taxes plus interest.
The IFTA site itself warns that posted exemption information “may NOT be the most recent available” and tells carriers to verify with each jurisdiction before filing.3International Fuel Tax Association. Carrier Information Treat the matrix as a starting point and confirm directly.
Records That Support an Exemption Claim
Every exemption survives or fails on documentation. IFTA requires distance records for every vehicle in the fleet covering all miles driven — loaded, unloaded, personal, and exempt. Section P540 of the IFTA Procedures Manual specifies what those records must contain:
- Beginning and ending dates of each trip
- Trip origin and destination
- Route of travel
- Beginning and ending odometer, hubodometer, or engine control module readings
- Total trip distance
- Distance in each jurisdiction
- VIN or unit number
Many carriers capture this on the IFTA-101 form or a jurisdictional equivalent, which includes a dedicated column for exempt miles. Filling that column correctly means cross-referencing your trip logs against the exemption rules for each jurisdiction on the route.4International Fuel Tax Association. IFTA Procedures Manual
Retain these records for at least four years from the date the tax return was due or filed, whichever is later. Some circumstances extend the period; Procedures Manual section P510 covers the exceptions. Discarding records early is one of the fastest ways to lose an audit.
GPS and Vehicle Tracking Requirements
GPS records are especially useful for off-highway exemption claims because a pin showing your truck on a construction site 300 yards from the nearest public road is far more persuasive than a handwritten “3 miles off-highway.” The Procedures Manual imposes its own technical requirements when GPS replaces manual trip reports. The system must create a record at least every 10 minutes when the engine is running, and each reading must include the date and time, latitude and longitude to at least four decimal places, the ECM odometer reading, and the VIN.4International Fuel Tax Association. IFTA Procedures Manual
Data has to be stored in an electronic spreadsheet format such as CSV or Excel. Static image formats — PDFs, JPEGs, Word documents — are not acceptable, even if they contain the same information. If your ELD or fleet platform doesn’t export in a compliant format, you may need parallel manual records. The four-year retention rule applies to GPS data too.
Reporting Exempt Miles on the Return
Once mileage records are complete, the information goes on the IFTA-100 quarterly return. Most base jurisdictions offer online filing; some still accept mailed returns. For each jurisdiction, you enter total distance and exempt distance, and the system calculates net taxable miles. Overpayments in one jurisdiction and underpayments in another net out into a single payment or refund.
The exempt column is where jurisdictional variation shows up in your filing. Miles you drove in a jurisdiction that recognizes off-highway exemptions go in as exempt; the same off-highway miles driven the next state over stay taxable. If your bookkeeping treats exempt miles as a fleet-wide bucket rather than a per-jurisdiction figure, the return won’t reconcile.
How Auditors Handle Exempt-Mile Claims
IFTA audits center on distance accounting, because jurisdictional distance allocation drives the entire tax calculation. Auditors select at least three representative months and trace your routes to verify that miles were reported to the correct jurisdictions and that exempt miles were properly supported.5International Fuel Tax Association. IFTA Audit Manual
The burden of proof is on you. The auditor isn’t required to prove your records are wrong; you’re required to prove they’re right. If documentation is incomplete or inconsistent, the base jurisdiction can estimate fuel use from industry averages, prior filing history, or fuel distributor data, and those estimates typically produce higher liability than accurate records would.5International Fuel Tax Association. IFTA Audit Manual
Exemption claims get particular scrutiny. If you reported 500 exempt off-highway miles in a quarter but can’t produce GPS data, odometer readings, or trip logs pinpointing where those miles occurred, the auditor will reclassify them as taxable and assess the tax plus interest back to the original due date. Carriers who claim exemptions without records tend to see the auditor again.
The takeaway is straightforward. Know which categories each jurisdiction on your route recognizes, log every exempt segment with the seven data points the Procedures Manual requires, keep GPS output in a spreadsheet format, and file each quarter with the exempt column allocated by jurisdiction rather than fleet-wide. That’s what turns a plausible exemption into one that survives.