Free Tool
IFTA Fuel Tax Calculator
Work out your quarterly International Fuel Tax Agreement (IFTA) return in one place. Enter the miles you drove and the fuel you bought in each state or province, add the current tax rate from the official IFTA rate matrix, and the calculator returns your fleet miles per gallon, taxable gallons per jurisdiction, and the net fuel tax you owe or the credit you have earned. Nothing is stored, and the math runs entirely in your browser.
Total miles
0
Total gallons
0.0
Fleet MPG
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| Jurisdiction | Miles | Gallons bought | Tax rate ($/gal) | Taxable gal | Net gal | Tax due / credit | |
|---|---|---|---|---|---|---|---|
| — | — | — | |||||
| — | — | — | |||||
| — | — | — |
Net IFTA tax owed
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Enter each jurisdiction's current tax rate from the official IFTA rate matrix for the quarter you are filing. A negative tax due is a credit. Surcharge states such as Indiana, Kentucky, and Virginia use a separate surcharge line: add another row for that jurisdiction and enter the surcharge rate. This tool covers the standard single fuel calculation and does not replace your base jurisdiction's return.
How IFTA fuel tax is calculated
IFTA settles the fuel tax between the states and provinces you run through, so you pay each one for the fuel you actually burned there. The calculation is the same everywhere. First your fleet miles per gallon is your total miles divided by your total gallons. Then, for each jurisdiction, your taxable gallons are the miles you drove there divided by that fleet MPG. Subtract the gallons you already bought and paid tax on in that jurisdiction, multiply what is left by that jurisdiction's tax rate, and you have the tax you owe or the credit you are due. Add every jurisdiction together for your net quarterly liability.
Rates change every quarter, which is why you enter them yourself from the current official IFTA rate sheet rather than trusting a figure that may be out of date. Learn the full picture in our complete IFTA guide, and see how IFTA sits alongside registration in the IRP guide and our IFTA, IRP and 2290 comparison.
Keep your trucks legal on every tax
IFTA is only one of the filings that keep a heavy truck on the road. The federal Heavy Vehicle Use Tax on Form 2290 is due once a year, and your stamped Schedule 1 is what your state asks for at registration. Consulics is an IRS Authorized e-file provider, so once your fuel taxes are squared away you can e-file Form 2290 and have your Schedule 1 back within minutes.
More free tools: IFTA deadline tracker · HVUT 2290 calculator · 2290 due-date checker · MCS-150 due-date checker.
How to calculate your IFTA fuel tax
The International Fuel Tax Agreement, or IFTA, lets an interstate carrier file one quarterly return that settles the fuel tax owed across every state and province it runs through. The math looks intimidating, but it comes down to a few steps, and this calculator does them for you once you enter your miles, your fuel, and the current rates.
The four numbers you need
- Miles driven in each jurisdiction during the quarter, from your trip records, ELD, or GPS.
- Gallons of fuel bought in each jurisdiction, from your fuel receipts.
- The current tax rate for each jurisdiction, taken from the official IFTA rate matrix for that quarter.
- Your totals, which the calculator uses to work out your fleet miles per gallon.
How the calculation works
Your fleet miles per gallon is total miles divided by total gallons. For each jurisdiction, taxable gallons are the miles you drove there divided by that fleet MPG. Subtract the gallons you already bought and paid tax on in that jurisdiction, and the result is your net taxable gallons. Multiply that by the jurisdiction rate to get the tax you owe there, or a credit if you bought more fuel than you burned. Add every jurisdiction together for your net quarterly liability.
Why you enter the rates yourself
IFTA rates are reset every quarter and differ by fuel type, and some jurisdictions add a separate surcharge. Rather than store figures that go out of date, this tool asks you to enter the current rate from the official rate sheet, so the result always reflects the quarter you are actually filing.
IFTA is separate from your Form 2290
IFTA is a quarterly fuel tax filed with your base jurisdiction. Form 2290 is the once a year federal Heavy Vehicle Use Tax filed with the IRS, and its stamped Schedule 1 is what your state wants at registration. Most interstate carriers handle both, plus IRP apportioned registration. When your fuel taxes are done, you can e-file Form 2290 with Consulics and get your Schedule 1 within minutes.
Frequently asked questions
What is a taxable gallon in IFTA?
It is the fuel your engine actually used in a jurisdiction, calculated as the miles you drove there divided by your fleet miles per gallon. It is not the fuel you bought there. You compare taxable gallons against purchased gallons to see whether you owe tax or have a credit.
How is fleet MPG figured for IFTA?
Fleet miles per gallon is your total miles across all jurisdictions divided by your total gallons purchased across all jurisdictions for the quarter. IFTA uses one blended fleet average, not a separate figure per truck.
Why does the calculator ask me to enter the tax rate?
IFTA fuel tax rates change every quarter and vary by jurisdiction and fuel type. Entering the current rate from the official IFTA rate matrix keeps the result accurate for the exact quarter you are filing instead of relying on a stored rate that may be stale.
Do I still have to file if I show a credit?
Yes. IFTA licensees file every quarter, even a zero return or a quarter that nets to a credit. Skipping a quarter can trigger penalties and put your IFTA license at risk.
Does this calculator handle surcharge states?
It handles the standard fuel tax calculation. For surcharge jurisdictions such as Indiana, Kentucky, and Virginia, add a separate row for that jurisdiction and enter the surcharge rate, since the surcharge is reported on its own line on the return.
Keep going
This tool and the information here are general guidance based on IRS publications, not tax or legal advice. Amounts and rules can change. Always confirm current details with the IRS or a qualified professional.
Important: verify before you rely on this
This calculator and the guidance around it are provided for general information only and do not constitute tax, legal, or accounting advice. IFTA fuel tax rates, surcharges, filing procedures, and jurisdiction requirements change frequently and can differ from one base jurisdiction to another. The figures produced here depend entirely on the numbers and rates you enter, and results are estimates intended to help you prepare, not a substitute for your official quarterly return.
It remains your responsibility to confirm every rate, deadline, and requirement with your base jurisdiction, the relevant Department of Motor Vehicles or Department of Revenue, the IRS, or a qualified tax professional before you file or make a payment. Consulics does not warrant that the information here is accurate, complete, or current, and accepts no responsibility for any outdated figures, errors, or actions taken in reliance on this tool. When in doubt, always defer to the official source for your jurisdiction.