IFTA is administrative rather than complicated, but it punishes sloppy record-keeping specifically. The filing itself is a few hours. Reconstructing a quarter of mileage and fuel because nobody captured it as it happened is the expensive part.
The short answer
The International Fuel Tax Agreement is an arrangement among US states and Canadian provinces. Instead of a qualifying interstate carrier filing fuel tax separately with every jurisdiction it operated in, it files one consolidated quarterly return with its base jurisdiction, which then settles between jurisdictions on the carrier's behalf.
The trade for that convenience is record-keeping. To calculate what is owed where, the return needs:
- Distance travelled in each jurisdiction, per qualifying vehicle
- Fuel purchased in each jurisdiction, with tax paid at the pump
The broad logic is that tax follows consumption — apportioned using where you drove — while credit is given for fuel tax you already paid when buying. Whether you owe or are owed comes out of the difference between those two.
Rates differ by jurisdiction and change over time, and the specific criteria for which vehicles qualify are defined by the agreement and administered by your base jurisdiction. Confirm current rates, qualification criteria and filing deadlines with your base jurisdiction rather than working from memory.
What goes wrong
Almost every IFTA problem is a data problem that started months earlier.
Mileage reconstructed after the fact. Estimating distance by jurisdiction from memory or from a routing tool at quarter-end is guesswork dressed as a record. It is also the thing least likely to survive an audit.
Fuel receipts that never arrived. A purchase with no record is one you cannot claim credit for. Card transaction data is far more reliable than paper collected from cabs, because it arrives whether or not anyone remembered.
Personal or off-road use mixed in. If a qualifying vehicle's distance includes travel that should be treated differently, it needs to be identified when it happens, not untangled later.
Records that do not reconcile. Distance that disagrees with fuel consumed, or with toll and ELD data, invites exactly the scrutiny you want to avoid. Internal consistency across your own records matters as much as any single figure.
Make it a by-product, not a project
The carriers for whom IFTA is painless are not more diligent at quarter-end. They capture the inputs continuously:
Fuel by card, imported automatically. Card transactions carry the jurisdiction, gallons and amount without anyone typing them. Receipt collection becomes a backup rather than the primary source.
Distance captured per jurisdiction as it accrues. Telematics that already records movement can support this. The alternative — deriving it from trip records at the end — is both more work and easier to get wrong.
A quarter that can be assembled at any time. If you can produce a draft return in the middle of a quarter, you will find the gaps while they are still fixable. If you can only produce one at the deadline, you find them under time pressure.
Retention and audit
Supporting records must be retained, and a filing is a claim you may be asked to substantiate. The practical standard is that someone should be able to trace a number on the return back to the underlying transactions and distance records without your help.
Confirm the current retention period and the level of detail expected with your base jurisdiction — this is one of the details that varies and that people most often get from an out-of-date source.
Where the software fits
IFTA is a reporting output of data you are already generating: where the trucks went, and where the fuel was bought.
TFS Fleet imports fuel card transactions, tracks distance by jurisdiction from telematics, and generates per-quarter IFTA reports with per-jurisdiction miles and taxable gallons — with amendment support when a quarter changes, and a mark-as-filed lock so a submitted return is not quietly edited afterwards.
See Fuel & IFTA and Fleet & Telematics.