Illinois IFTA Fuel Tax Rate, 3rd Quarter 2025
Illinois's IFTA diesel rate for the 3rd quarter of 2025 is $0.7490 per gallon, up $0.0130 from Q2 2025.
Illinois rate for Q3 2025
Special diesel, Q3 2025
$0.7490
per US gallon, up $0.0130 from Q2 2025
- Diesel tax rate
- $0.7490/gal
- Surcharge
- None listed
- Quarter
- Q3 2025, from Jul 1, 2025
- Change vs last quarter
- up $0.0130
Notes from the source
Matrix footnote #26 (ILLINOIS): LNG and Propane are taxed per diesel gallon equivalent (DGE) beginning July 1, 2017. LNG is taxed at the rate shown per diesel gallon equivalent (DGE), with one DGE equal to 6.06 pounds of LNG. Propane is taxed at the rate shown per diesel gallon equivalent (DGE) with one DGE equal to 6.41 pounds of propane. Multiply IL taxable and tax paid propane gallons by 0.651 to determine the DGEs subject to the Illinois rate. CNG is taxed at the rate shown per gasoline gallon equivalent (GGE), with one GGE equal to 5.66 pounds of compressed natural gas. All other fuels are taxed at the rates shown per gallon. For further information, see Informational Bulletin FY 2017-15, available on our website at tax.illinois.gov.
Worked example: the Illinois line of your IFTA return
Change the numbers to match your quarter. Prefilled with 10,000 total miles on 1,550 gallons, 1,200 of those miles in Illinois, and 100 gallons bought there.
Illinois vs. its neighbors, Q3 2025
| Jurisdiction | Diesel + surcharge | vs. IL |
|---|---|---|
| Illinois | $0.7490 | — |
| Indiana | $0.6100 | −$0.1390 |
| Wisconsin | $0.3290 | −$0.4200 |
| Iowa | $0.3250 | −$0.4240 |
| Kentucky | $0.3250 | −$0.4240 |
| Missouri | $0.2950 | −$0.4540 |
On an IFTA return, a higher rate doesn't mean you pay more overall. Fuel you buy in a high-rate state earns a bigger credit. What matters is where you burn the fuel versus where you buy it.
Illinois rate, last 4 quarters
Source: IFTA, Inc. Fuel Tax Rate Matrix, 3rd Quarter 2025 · Effective Jul 1, 2025 · Last verified Sep 28, 2026
IFTA, Inc. publishes the rates each member jurisdiction reports. Illinois's tax agency is the final word on its rate.
Estimates for planning. Confirm with your tax pro or your base jurisdiction's IFTA office before filing.