IFTA Filing Guide

IFTA returns are filed quarterly with your base jurisdiction, due the last day of the month after the quarter ends: 30 April, 31 July, 31 October and 31 January. You file even when the truck did not move, and you keep the underlying records for four years.

Who has to file

IFTA — the International Fuel Tax Agreement — is a cooperative arrangement between the 48 contiguous US states and 10 Canadian provinces, 58 jurisdictions in total. Alaska, Hawaii, the District of Columbia and the Canadian territories are not members.

It applies to qualified motor vehicles operating in more than one member jurisdiction. The definition turns on weight and axles: broadly, vehicles over 26,000 pounds gross vehicle weight or registered gross weight, or with three or more axles regardless of weight, or used in combination where the combined weight exceeds 26,000 pounds. Recreational vehicles are excluded.

Run only inside your own state and IFTA does not apply — that state's own fuel tax rules do instead. Cross a single member border in a qualified vehicle and you need a license, decals and a quarterly return.

The point of the whole arrangement is administrative. Before IFTA, a carrier crossing eight states filed with eight states. Now you file one return with your base jurisdiction, they collect or refund the net, and the money is distributed between jurisdictions behind the scenes.

The four deadlines

Where a due date lands on a weekend or a legal holiday it normally moves to the next business day, but do not build a habit on that. Filing and payment are both due — a return submitted on time with the money following later is still a late payment, and interest runs from the due date.

License renewal is annual and separate. Decals are issued for the calendar year, and most jurisdictions allow a grace period into the new year for displaying the previous year's decals. Check your base jurisdiction rather than assuming the length of it.

What goes on the return

Per fuel type, per jurisdiction: the miles you ran there, and the gallons you bought there. From those two columns everything else is derived.

1. Fleet MPG — total miles across all jurisdictions divided by total gallons purchased across all jurisdictions. One figure for the whole quarter.
2. Taxable gallons per jurisdiction — miles there divided by the fleet MPG.
3. Net taxable gallons — taxable gallons minus the tax-paid gallons you bought there. Negative is a credit.
4. Tax due per jurisdiction — net taxable gallons times that jurisdiction's rate for the quarter.
5. Surcharges where a jurisdiction levies one, calculated on taxable gallons with no credit for purchases.
6. Net position — everything summed. Credits in one jurisdiction offset tax owed in another.

The IFTA calculator does that arithmetic across all 58 jurisdictions and exports the quarter as a CSV you can check line by line against the return before you submit it.

Fuel types are reported separately. A mixed fleet running diesel and CNG files them as separate schedules, not blended together, because they are taxed differently.

The records you must keep

This is where audits are decided. The return is arithmetic; the records are the evidence, and an auditor who cannot reconcile them will reconstruct your liability in a way you will not enjoy.

Distance records

For every trip, the record needs to show the date, where it started and ended, the route taken, beginning and ending odometer readings, total trip miles, the miles broken down by jurisdiction, and which vehicle and licensee it belonged to.

GPS and ELD data is accepted where it produces that detail. The catch is that "we have the data" and "the data contains the required fields, retained for four years, exportable" are different statements. Check what your provider actually keeps and for how long — a subscription lapse that takes the historical data with it is a real and recoverable disaster only if you noticed in time.

Fuel records

Every gallon you claim as tax-paid needs a receipt showing the date, the seller's name and location, the number of gallons, the fuel type, the price or total, and the vehicle it went into.

A receipt missing the unit number is the classic failure. Without it an auditor can disallow the purchase, which does not just remove a credit — it increases the tax you owe, because those gallons no longer offset your taxable gallons in that jurisdiction. Bulk fuel from your own tank has extra requirements: withdrawal records per vehicle, inventory reconciliation, and proof that tax was paid on the bulk purchase.

How long

Four years from the return due date or the filing date, whichever is later. Keep distance and fuel records together by quarter. Digital is fine and generally easier to produce than a box of faded thermal paper.

Audits and what actually triggers them

Jurisdictions audit a proportion of licensees as routine, so selection is not an accusation. Some things do raise the odds.

• An implausible fleet MPG. Far outside the range the equipment could achieve is the loudest signal there is, and it is nearly always a data error rather than fraud — a transposed odometer reading, miles entered in a gallons column, a missing fuel receipt.
• MPG that swings between quarters. A fleet that reports 6.8, 7.1, 4.2 then 9.6 is describing a bookkeeping problem, not a fuel efficiency program.
• Gallons claimed where no miles were reported. Fuel bought in a jurisdiction the truck apparently never entered.
• Round numbers everywhere. Real mileage does not end in zeroes across an entire return.
• Repeated late filings. They attract attention beyond the penalty itself.
• Returns that do not reconcile with your own logs or with what enforcement observed at a scale.

The best defense is boring: file on time, keep the records where you can find them, and check the MPG before you submit. The calculator flags an implausible fleet MPG for exactly that reason — catching it before filing is free, and catching it in an audit is not.

Penalties and interest

The standard IFTA provision is a penalty of $50 or ten per cent of the net tax due, whichever is greater. Note that it applies to a late return even when the return shows a credit, so "I was getting money back, so it did not matter" is not a defense.

Interest accrues on unpaid tax on a per-jurisdiction basis until it is paid. Your base jurisdiction sets the mechanics and can vary the detail, so treat these as the standard provisions and confirm with them.

The more serious consequence is not financial. Persistent failure to file, failure to pay or failure to produce records can lead to revocation of the license, and operating a qualified vehicle interjurisdictionally without a valid IFTA license and decals is an enforcement problem in every member jurisdiction you enter. That is a roadside problem, not a paperwork one.

Common filing mistakes

• Not filing a zero return. A quarter with no operations still needs a return.
• Forgetting a jurisdiction. Clipping the corner of a state still counts. Total miles on the return should reconcile with total miles on the logs.
• Using pump price instead of gallons. IFTA is calculated on volume, not dollars.
• Blending fuel types. Diesel and CNG file separately.
• Rounding at every step. Round at the end. Rounding gallons to whole numbers per jurisdiction accumulates a meaningful error across a busy quarter.
• Personal conveyance and deadhead miles. They are still miles in a jurisdiction. Empty does not mean exempt.
• Assuming a mid-quarter rate change does not exist. Where a jurisdiction changed its rate part way through a quarter, the return may need it split. Check the instructions rather than the habit.

A filing routine that works

1. Weekly, collect fuel receipts and check each one has a unit number on it. Chasing a receipt a week later is possible; chasing it in April is not.
2. Monthly, pull mileage by jurisdiction from your ELD or logs and reconcile the total against the odometer.
3. At quarter end, total the miles and gallons, calculate the fleet MPG and look at it. If it is not what you expected, find out why before going further.
4. Get the current rates from the official IFTA quarterly matrix for the quarter you are filing.
5. Run the numbers in the quarterly calculator, export the CSV and keep it with the quarter's records.
6. File and pay together, before the deadline rather than on it.

Fuel tax sits alongside the rest of the paperwork around a load — the delivery receipts, the lumper receipts, the invoices. If you are here for those instead, the free bill of lading generator and the other document tools are on the front page.

Where to get the authoritative answer

This is a practical guide, not tax advice, and it describes the general shape of an arrangement that individual jurisdictions administer with local variations. Your base jurisdiction's IFTA office is the authority on your license, your deadlines and your penalties. The IFTA, Inc. quarterly rate matrix is the authority on rates. Where those disagree with anything on this page, they are right.

Common questions