IFTA Quarterly Return Common Errors and How to Fix Them

What changed

IFTA, Inc. released Q4 2025 audit findings on December 22, 2025. Across 12 base-jurisdiction audits sampled, 43% of audited returns used a stale tax-rate matrix (the prior quarter's rates instead of the filed quarter's), 28% had inadequate trip-record documentation for the reported miles, and 15% had math errors on the per-jurisdiction summary.

These are all auditor-side findings - the carrier may have filed in good faith but the working-paper trail did not support the numbers reported.

How to avoid the stale-rate error

IFTA rate matrices are published quarterly at iftach.org. The rates change frequently, especially for non-diesel fuels (LNG, CNG, propane). Most carrier IFTA software pulls the rate automatically - but only if the software is configured to refresh on each return generation.

Manual filers should cross-check rates against the iftach.org current matrix every quarter. The most common mistake is using the prior-quarter matrix for the new quarter.

How to fix trip-record gaps

IFTA §R1010 requires source-document support for every reported state-by-state mile. Acceptable records: ELD-generated state-line crossings, driver trip sheets, fuel receipts with origin / destination annotation, dispatch logs.

Modern ELDs that capture state-line geofencing are the cleanest source. Manual trip sheets work but require disciplined fill-out and matched fuel receipts.

What to do next

Pull your last-quarter IFTA return. Verify the tax-rate matrix matches the iftach.org rates for that quarter. Spot-check 3-5 trips against ELD or trip-sheet records. Fix any errors via amended return through your base jurisdiction. Our /guides/ifta-filing-complete-guide page covers the full IFTA workflow.