IFTA reporting: what mileage records you actually need

The International Fuel Tax Agreement — IFTA — exists so an interstate carrier files one quarterly fuel tax return with its base state instead of separate returns with every state it rolled through. The concept is simple. The recordkeeping is where fleets get hurt.

Who IFTA applies to

IFTA generally covers vehicles used in interstate commerce that exceed 26,000 lbs gross vehicle weight, have three or more axles, or are used in combination above that weight. Local fleets that never leave the state, and lighter service vehicles, are typically outside it — another thing the big vendors' marketing tends to blur.

What the quarterly return needs

• Total miles traveled in each member state or province, per vehicle
• Total fuel purchased in each state, with receipts
• Fleet miles-per-gallon calculated from those totals
• Records retained for audit — typically four years

Where fleets go wrong

Auditors don't take your word for state-line splits. Handwritten trip sheets with rounded numbers, gaps between odometer readings, and missing intrastate movements are the classic audit findings — and an IFTA audit that finds unreliable records can assess tax on estimated mileage that is never estimated in your favor.

What GPS tracking changes

A GPS-tracked fleet generates the distance side of IFTA automatically: every mile, attributed to the right state by actual position data, summarized by quarter, retained for the audit window. Nexus produces mileage-by-state reports that support your IFTA filing — you or your tax service still file the return, but the data arrives done instead of decoded from paper logs.