IFTA Calculator
Estimate your quarterly IFTA fuel tax liability by state. Enter miles driven and gallons purchased in each jurisdiction.
Used to calculate taxable gallons per state (miles / MPG).
State-by-State Mileage & Fuel
| State | Miles Driven | Gallons Purchased | Tax Rate/Gal | |
|---|---|---|---|---|
| $0.200 | ||||
| $0.190 | ||||
| $0.285 |
Rate: $0.200/gal
Rate: $0.190/gal
Rate: $0.285/gal
Total Miles
2,800
Total Gallons Purchased
250
Total Taxable Gallons
430.8
Net Tax Owed / Credit
$31
IFTA Tax Breakdown by State
| State | Miles | Gallons Purchased | Taxable Gallons | Net Gallons | Rate | Tax / Credit |
|---|---|---|---|---|---|---|
| Texas | 2,000 | 150 | 307.7 | 157.7 | $0.200 | $31.54 |
| Oklahoma | 500 | 0 | 76.9 | 76.9 | $0.190 | $14.62 |
| Arkansas | 300 | 100 | 46.2 | -53.8 | $0.285 | -$15.35 |
| Total | 2,800 | 250 | 430.8 | 180.8 | $30.81 |
Tax rates are approximate and based on published IFTA rates. Actual rates may vary by quarter. Always verify with your state's IFTA office.
Frequently Asked Questions
IFTA (International Fuel Tax Agreement) is a tax agreement among US states and Canadian provinces that simplifies fuel tax reporting for interstate carriers. You need IFTA credentials if you operate a qualified motor vehicle (26,000+ lbs or 3+ axles) in two or more IFTA jurisdictions.
IFTA divides total fuel consumed among jurisdictions based on miles driven in each. Taxable gallons for a state = (miles in that state / fleet MPG). If you purchased more fuel in a state than your taxable gallons, you get a credit. If you purchased less, you owe tax. The net is multiplied by each state's fuel tax rate.
IFTA returns are filed quarterly: Q1 (Jan-Mar) due April 30, Q2 (Apr-Jun) due July 31, Q3 (Jul-Sep) due October 31, Q4 (Oct-Dec) due January 31. Late filings incur penalties and interest.
California and Pennsylvania consistently have the highest diesel fuel tax rates, often exceeding $0.50 per gallon. Indiana and Washington also have notably high rates. Rates change quarterly, so always verify with the current IFTA rate schedule before filing.
Yes. If you purchased more fuel in high-tax states than you consumed there (based on miles driven), you will receive credits. These credits offset taxes owed to other states. If your total credits exceed taxes owed, you receive a net refund.