IFTA calculator
Enter miles and diesel gallons bought in each state to get fleet MPG, tax, credit and net per state.
Filled with an example trip — replace it with your own states, miles and gallons.
- Oklahoma$2.28
- Rate
- $0.19
- Taxable gal
- 112
- Tax
- $21.28
- Credit
- $19.00
- Texas$2.40 credit
- Rate
- $0.20
- Taxable gal
- 288
- Tax
- $57.60
- Credit
- $60.00
- Total tax $78.88Total credit $79.00
Estimate only, using Q4 2026 diesel rates. Oregon shows $0 (weight-mile tax state). Verify with your base jurisdiction before filing.
- Net estimate
- $0.12 credit
- Total miles
- 2,500
- Total gallons
- 400.0
- Fleet MPG
- 6.25
How the estimate works
- Fleet MPG = total miles ÷ total gallons, rounded to two decimals.
- Taxable gallons in a state = miles in that state ÷ fleet MPG.
- Tax = taxable gallons × (state diesel rate + surcharge, if any).
- Credit = gallons bought in that state × state diesel rate. Surcharges earn no credit.
- Net = tax − credit. A positive number is owed; a negative number is a credit.
This is an estimate, not a filing. It leaves out things a real return may include, such as tax-paid vs. non-tax-paid gallons, exempt miles, penalties, interest and Canadian jurisdictions. Rates for each quarter are listed on the IFTA rates pages.
Verify with your base jurisdiction before filing.
When the return is due
IFTA returns are due on the last day of the month after each quarter (April 30, July 31, October 31, January 31), or the next business day when that falls on a weekend. Exact dates and the next deadline are on the IFTA due dates page.
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freightline does this automatically from your ELD miles and fuel receipts
Miles by state come from your loads and ELD, gallons from fuel-card imports and receipts, and the quarter’s rates are already loaded. Try it on your own trucks free for 30 days, no credit card.
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