IFTA penalties
The headline penalty is small — $50 or 10% of the net tax due, whichever is greater. The expensive part is never the penalty. It is what happens when an auditor decides your records cannot support the numbers you filed.
What it costs, in order of severity
| What | Cost |
|---|---|
| Late or missing return | $50 or 10% of net tax due, whichever is greater — per return |
| Late payment | Interest per jurisdiction, accruing monthly until paid |
| Repeated failures | Suspension or revocation of the IFTA licence |
| Running without valid credentials | Citations and fines at roadside, per jurisdiction |
| Audit with inadequate records | Your mpg replaced with a standard figure and every quarter under review recalculated |
Why the last row is the one to care about
An auditor who cannot tie your reported miles to source records does not simply disallow the difference. They can rebuild the return using a standard mpg, and because taxable gallons are miles ÷ mpg, a lower standard mpg increases taxable gallons in every jurisdiction at once. Applied across four to sixteen quarters, a $50 penalty becomes a five-figure assessment.
Which is why distance records matter more than the arithmetic does. The arithmetic is easy; the evidence is the job.
What raises your odds of being audited
- Implausible fleet mpg. A quarter at 9 mpg or 4 mpg invites the question.
- Jurisdiction miles that don't sum to total miles. It is the first arithmetic check anyone does.
- Mpg that moves sharply quarter to quarter without the fleet changing.
- Chronic late filing. It marks the account.
- Large refund claims. Legitimate ones happen; they are checked.
Staying out of trouble
- File in the first week after the quarter ends, while the receipts are still in front of you — see due dates.
- File a zero return for quiet quarters. It costs nothing and skipping it costs $50.
- Reconcile before you file. Jurisdiction miles to total miles, fuel to receipts, mpg to plausibility.
- Keep everything four years from the later of the due date and the filing date.
- If you're late, file anyway, immediately. The penalty is fixed; the interest is not.
Questions
What is the penalty for filing IFTA late?
$50 or 10% of the net tax due, whichever is greater. On a zero return that is a flat $50 for a form nobody would have read.
Is there interest as well?
Yes, and it accrues per jurisdiction on the tax owed to that jurisdiction, month by month until it is paid. Small on a small balance, and genuinely annoying on several quarters of an unfiled return.
Can my IFTA licence be revoked?
Yes. Base jurisdictions suspend or revoke licences for repeated late filing or unpaid balances. Running a qualified motor vehicle interstate without valid credentials is a roadside problem, not a paperwork one.
What triggers an IFTA audit?
Jurisdictions audit a percentage of licensees routinely, so some of it is chance. What raises your odds is a fleet mpg that is implausible or that jumps around, jurisdiction miles that do not reconcile with total miles, and returns that are consistently late.
What happens in an audit?
They test whether your reported distance and fuel can be traced to source records. If it cannot, they can reconstruct your return using a standard mpg, which almost always increases what you owe — across every quarter under review.