FY 2026-14 Change in the Motor Fuel Use Tax Rate, Effective January 1, 2026, through June 30, 2026

To: All International Fuel Tax Agreement (IFTA) Licensees

Illinois Motor Fuel Use Tax is comprised of two parts, Part A and Part B. 35 ILCS 505/13a. This tax is reported and paid by licensees under the International Fuel Tax Agreement (IFTA). The rates listed here are effective January 1, 2026, through June 30, 2026, for use on the quarterly IFTA returns.

The Part A rate is the motor fuel tax rate established by Section 2 of the Motor Fuel Tax Law, which imposes the tax per gallon on all motor fuel used in motor vehicles operating on Illinois public highways and in recreational type watercraft operating on Illinois waters. 35 ILCS 505/2.

From January 1, 2026, through June 30, 2026, the Part A tax rates (in cents per gallon, DGE¹, or GGE²) are as follows:

        Diesel³                     55.8¢ per gallon

        Gasoline⁴                 48.3¢ per gallon

        LPG                          55.8¢ per DGE⁵

        LNG                         55.8¢ per DGE⁶

        CNG                         48.3¢ per GGE⁷

The Illinois Department of Revenue is required to establish the Part B rate of the Motor Fuel Use Tax for diesel fuel, gasoline, gasohol, liquefied petroleum gas (LPG, commonly known as propane), compressed natural gas (CNG), and liquefied natural gas (LNG).

The Part B rate is established by the Department as of January 1 of each year using the average selling price per gallon of motor fuel sold in Illinois during the previous 12 months and multiplying it by 6.25 percent to determine the cents per gallon rate. 35 ILCS 505/13a(2).

From January 1, 2026, through December 31, 2026, the Part B tax rates (in cents per gallon, DGE¹, or GGE²) are as follows:

        Diesel³                     18.0¢ per gallon

        Gasoline⁴                 17.0¢ per gallon

        LPG                          16.2¢ per DGE⁵

        LNG                         14.4¢ per DGE⁶

        CNG                         11.5¢ per GGE⁷

From January 1, 2026, through June 30, 2026, the Motor Fuel Use Tax rates for the fuels listed below are as follows:           

Rate information is available at tax.illinois.gov. Use MyTax Illinois at mytax.illinois.gov to renew your IFTA license, order decals, and file and pay quarterly returns.

¹ “DGE” means diesel gallon equivalent. 35 ILCS 505/1.8.

² “GGE” means gasoline gallon equivalent. 35 ILCS 505/1.8.

³ Diesel fuel is defined as any product intended for use or offered for sale as a fuel for engines in which the fuel is injected into the combustion chamber and ignited by pressure without electric spark (includes biodiesel). 35 ILCS 505/2(b); 35 ILCS 105/3-41.

⁴ Gasoline includes gasohol. See 35 ILCS 105/3-40.

⁵ A DGE of LPG = 6.41 pounds of LPG. The conversion ratio used to calculate the LPG rate is one gallon = 0.651 DGEs of LPG. 35 ILCS 505/1.8A.

⁶ A DGE of LNG = 6.06 pounds of LNG. The conversion ratio used to calculate the LNG rate is one gallon = 0.5776 DGEs of LNG. 35 ILCS 505/1.8A.

⁷ A GGE of CNG = 5.66 pounds of CNG. 35 ILCS 505/1.8B.