Illinois Freezes Motor Fuel Use Tax Rate Hike for Interstate Truckers Through Year’s End
The Illinois Department of Revenue (IDOR) has reissued its motor fuel use tax bulletin for interstate commercial motor carriers.
The revision was prompted by Public Act 104-0468, signed into law on June 16, 2026, which suspended the scheduled Consumer Price Index (CPI) adjustment to the motor fuel tax rate for a six-month window running from July 1 through December 31, 2026. This move came after the average gallon of regular gas in Illinois hit $4.62, up from $3.36 a year earlier.
Illinois’ Motor Fuel Use Tax is calculated in two parts. “Part A” is set by state statute and ordinarily rises each July 1 in line with the prior year’s CPI. “Part B” is established by IDOR annually based on the average selling price of motor fuel in Illinois during the previous 12 months .
Under the suspension, the “Part A” rates that would have risen with inflation are instead held at their existing levels through the end of the year. The automatic CPI adjustment has been a feature of Illinois motor fuel taxation since the 2019 “Rebuild Illinois” infrastructure program signed by Gov. J.B. Pritzker, which also doubled the base rate from 19 cents per gallon. The newly effective rates for interstate commercial motor vehicles from July 1 through December 31, 2026 are:
The freeze applies only through December 31, 2026. The IDOR has not announced what rate adjustments, if any, are planned for January 1, 2027.
