Free IFTA calculator · 3rd quarter 2026 rates
IFTA fuel tax calculator
Miles and tax-paid gallons per state in; fleet MPG, taxable gallons, tax, surcharge and the total due out. One quarter, no account.
Sample data: a made-up quarter for one diesel truck, so you can see the result. Replace the lines with your own miles and fuel receipts.
Rates: IFTA, Inc. tax rate matrix 3Q2026, downloaded 2026-09-29 (iftach.org). Your numbers stay in this browser.
Result
- Total owed for 3Q2026
- $36.98
- Fleet MPG
- 6.52
- Total miles
- 8,080 mi
- Gallons used for MPG
- 1,240 gal
- Taxable gallons
- 1,239 gal
- Tax-paid gallons
- 1,240 gal
- Fuel tax (net)
- $22.97
- Surcharges
- $14.01
Positive = you owe it with the return; negative = a credit (your base jurisdiction decides refund or carry-forward). Estimates from the IFTA, Inc. tax rate matrix for the quarter shown. Not tax advice. File your return with your base jurisdiction and check its figures. Not affiliated with IFTA, Inc.
| Jur. | Taxable gal | Tax-paid gal | Net gal | Rate | Tax + surcharge |
|---|---|---|---|---|---|
| TX | 590 | 520 | 70 | $0.2000 | $14.00 |
| OK | 218 | 480 | -262 | $0.1900 | -$49.78 |
| AR | 147 | 100 | 47 | $0.2850 | $13.40 |
| TN | 186 | 140 | 46 | $0.2700 | $12.42 |
| VA | 98 | 0 | 98 | $0.3360+ $0.1430 surcharge | $46.94$32.93 + $14.01 |
| Total | 1,239 | 1,240 | -1 | $36.98 |
Rates per gallon from the matrix: TX $0.2000/gal, OK $0.1900/gal, AR $0.2850/gal, TN $0.2700/gal, VA $0.3360/gal.
Filing this quarter? Pro prints the worksheet.
Every jurisdiction line with its rate, the totals and the MPG on one printable sheet, an Excel file with live formulas and trip and fuel logs for next quarter.
The tools
IFTA tax calculator
Miles, taxable miles and tax-paid gallons per jurisdiction in; taxable gallons, net gallons, tax, surcharge and the total due or credit out.
IFTA due dates
The quarter a date falls in, its due date moved past weekends, the days left and what a late return costs.
Fleet MPG calculator
Miles and gallons per truck into the one fleet MPG the return uses, to two decimals.
How the IFTA return is worked out
- Fleet MPG = all miles in all jurisdictions divided by all gallons put in the trucks, to two decimals.
- Taxable gallons for each state or province = its taxable miles divided by that MPG, rounded to a whole gallon.
- Net taxable gallons = taxable gallons minus the tax-paid gallons you bought there. Negative means you paid more tax at the pump than you used: a credit.
- Tax = net taxable gallons x the jurisdiction's rate for the quarter from the IFTA, Inc. matrix; a surcharge, where the matrix lists one (Kentucky and Virginia on diesel this quarter), is due on every taxable gallon, with no credit.
Sample data: the starting quarter above covers 8,080 miles in 5 states at 6.52 MPG and comes to $36.98 with 3Q2026 rates. The highest diesel rates this quarter are California ($0.9790/gal), Pennsylvania ($0.7410/gal), Illinois ($0.7380/gal).
The 3rd quarter 2026 return is due Monday, November 2, 2026: the last day of the month after the quarter, moved to the next business day because Saturday, October 31, 2026 is a weekend. See the due date helper.
Where the rates come from
From the IFTA, Inc. tax rate matrix for 3rd quarter 2026 (3Q2026), the CSV published on the IFTA Tax Rate Download Center and downloaded 2026-09-29: 58 jurisdictions, US$ per gallon and CA$ per litre, with the surcharge rows. The rules (MPG to two decimals, due dates, penalty) are from the IFTA Articles of Agreement and Procedures Manual effective January 2026. Your miles and gallons stay in your browser: nothing is uploaded.
Estimates from the IFTA, Inc. tax rate matrix for the quarter shown. Not tax advice. File your return with your base jurisdiction and check its figures. Not affiliated with IFTA, Inc.
Filing this quarter? Pro prints the worksheet.
Every jurisdiction line with its rate, the totals and the MPG on one printable sheet, an Excel file with live formulas and trip and fuel logs for next quarter.
Frequently asked questions
- Is the IFTA calculator free?
- Yes, with no limit and no sign-up. Pro is a paid extra that prints the quarter as a worksheet, exports it to Excel with live formulas and adds trip and fuel log templates; the calculator itself does not change.
- Does this file my IFTA return?
- No. It works out the figures the return asks for so you can check them or copy them onto your base jurisdiction's return or its online filing system. You file and pay with your base jurisdiction.
- Which rates does it use?
- The IFTA, Inc. tax rate matrix for 3rd quarter 2026, downloaded 2026-09-29. Pick the quarter the miles were driven in; a new quarter is added when IFTA publishes its matrix.
- What if a state has no rate listed?
- Some jurisdictions list no rate for a fuel in the matrix (Oregon has none for diesel this quarter). Those lines carry no tax here, but their miles still count toward your fleet MPG. Check the matrix footnote and your base jurisdiction's instructions.
- Is my data stored anywhere?
- Only in this browser, so the page remembers your last quarter. No account, no upload, and the numbers you type are not sent to analytics.
Guides
- How to calculate IFTA tax, step by step (with a worked example)
Fleet MPG, taxable gallons per state, tax-paid credit, net gallons, rate and surcharge: the IFTA return worked through one sample quarter with 3Q2026 rates.
- IFTA fuel tax rates, 3rd quarter 2026: diesel and gasoline by state
Diesel and gasoline rates for all 58 IFTA jurisdictions in 3Q2026 from the IFTA, Inc. matrix, with the Kentucky and Virginia surcharges and the top 10.