IFTA Explained: What It Is, How It Works, and How to Stop Dreading It

IFTA — the International Fuel Tax Agreement — is a system that 48 US states and 10 Canadian provinces use to make sure fuel taxes end up with the states where the miles were actually driven. If you're an owner-operator crossing state lines, you're required to file quarterly.

The core idea

When you buy fuel in Texas, you pay Texas fuel tax at the pump. But if you drove 400 of those miles in Oklahoma and 300 in Kansas, Oklahoma and Kansas are owed a share of the tax on those miles. IFTA is the mechanism that moves money between states to settle those accounts.

Every quarter you file a return that shows:

• •How many miles you drove in each state
• •How many gallons you bought in each state
• •What your fleet MPG was
• •How many gallons you should have burned in each state based on your MPG
• •The net tax owed or credited per state

Some states you'll owe more (you drove more than you fueled there). Others you'll get a credit (you bought more fuel than you burned there). You pay the net difference — or get a refund.

What you need to track

To file accurately you need:

Fuel receipts for every fill-up. Date, location (state), gallons, price per gallon. This is why you should always get a paper receipt or email receipt — not just pay at the pump and drive.

Miles driven per state. Your ELD should track this automatically if you have one. If you're running paper logs, you need to record odometer readings at every state line.

Keep records for 4 years. IFTA audits can go back four years. Keep your receipts.

The quarterly deadlines

Missing a deadline means penalties and interest. Most states charge $50 or 10% of the amount owed — whichever is greater.

The part that trips people up

The calculation isn't hard, but doing it manually for 8–12 states every quarter is tedious and error-prone. The math is: consumed gallons per state = miles in state ÷ fleet MPG. Tax owed = consumed gallons × state tax rate. Net = tax owed − tax paid (fuel purchased in that state).

This is exactly the kind of work that should be done by software, not a spreadsheet. If you're tracking your fuel stops and state miles in OPHaul, the report tab calculates everything and generates a PDF you can hand straight to your accountant.