If you’re an owner-operator or small fleet running freight in and out of Chicago, you deal with city fuel taxes, a Lake Shore Drive truck ban, the No. 1 truck bottleneck in the country, and an Illinois diesel tax rate that changes twice a year. If your books don’t separate those costs, your cost per mile is a blend of everything and a true measure of nothing, and every rate you accept is measured against the wrong number.
Fuel Costs More Inside the City
Diesel is expensive everywhere right now. The U.S. Energy Information Administration put the Midwest average for on-highway diesel at $6.29 a gallon for the week of October 6, 2026, above the national average of $6.20.
Chicago adds to that. Stations inside city limits collect city and Cook County fuel taxes on top of the state tax. The Civic Federation’s 2026 guide to Chicago consumer taxes puts the combined motor fuel tax on a gallon of diesel bought in Chicago at about $0.94. That’s a big reason the same gallon costs more downtown than it does at a truck stop out on I-80.
For a carrier running local routes, that gap belongs in the books. If fuel bought in the city and fuel bought outside it all land in one fuel line, your cost per mile is a blended number that hides which lanes are eating your margin.
Fuel prices and tax rates in this section are as of October 2026 and change often.
Truck Rules Are Strict, and Mistakes Are Expensive
Commercial vehicles are banned from DuSable Lake Shore Drive, with a narrow exception for traffic to and from McCormick Place. The ban covers any vehicle designed or used to carry freight, not just big rigs.
Chicago is crisscrossed by railroad viaducts, and many have posted clearances below the 13’6″ of a standard van trailer. The Chicago Department of Transportation posts the clearance on a sign at each viaduct and publishes a full list of posted viaduct clearances. One wrong turn can mean a ticket, a towed truck, or a damaged trailer.
Then there’s congestion. The American Transportation Research Institute ranked the I-294/I-290/I-88 interchange west of the city as the No. 1 truck bottleneck in the country in its 2026 list. Hours spent sitting in traffic are hours on your clock that earn nothing.
In your books, these aren’t general operating expenses. A truck-route ticket, a Chicago Skyway toll or a viaduct repair belongs to the lane or the customer that caused it. That’s how you see whether a Chicago load actually pays.
IFTA When Illinois Is Your Base State
If Illinois is your base jurisdiction, you register for IFTA with the Illinois Department of Revenue through MyTax Illinois. Illinois is generally your base jurisdiction if:
Your qualified motor vehicles are registered in Illinois
You run the operation from an established place of business in Illinois (a P.O. box or virtual office doesn’t count)
Your operational records are kept in Illinois
Your vehicles travel on Illinois highways
IFTA returns are due quarterly, by the last day of the month after each quarter ends (April 30, July 31, October 31 and January 31). You have to file even if your trucks never left Illinois that quarter.
Illinois has one of the highest diesel tax rates in the country. For July 1 through December 31, 2026, the Illinois Motor Fuel Use Tax rate on diesel is 73.8 cents a gallon. Rates change twice a year, so your IFTA math has to use the rate for the quarter you’re filing.
We Don’t Have a Chicago Office. We Know Chicago’s Numbers.
COGS Bookkeeping is a remote bookkeeping service for owner-operators and small trucking fleets. What we bring is an understanding of how Chicago routes change your numbers, and books set up to show it.
Cost per mile by region. City and suburban fuel tracked separately, so you see what each lane really costs to run.
Route costs where they belong. Tolls, tickets and route damage tied to the lane or customer that caused them, not buried in overhead.
IFTA filed every quarter. Miles and fuel tracked by jurisdiction all quarter, so the return isn’t a scramble.
A P&L that shows which customers pay. Not just what they paid you, but what their loads cost you to run.
Know Your Chicago Cost Per Mile
If you run freight through Chicago and you’re not sure what your true cost per mile is, start with our free Cost-Per-Mile Calculator. It takes about ten minutes, needs no email, and gives you your number.
Want help reading it? Talk to us and we’ll walk through what it means for the loads you take.
Common Questions
Do I need a bookkeeper in Chicago?
No. COGS Bookkeeping works remotely with owner-operators and small fleets. You send settlements, fuel receipts and statements electronically, and you get your books, reports and IFTA filing back the same way.
When are Illinois IFTA returns due?
Quarterly, by the last day of the month after each quarter ends: April 30, July 31, October 31 and January 31. You must file even if your trucks did not leave Illinois that quarter.
What is the Illinois diesel tax rate for IFTA?
For July 1 through December 31, 2026, the Illinois Motor Fuel Use Tax rate on diesel is 73.8 cents per gallon. Illinois updates the rate twice a year, so use the rate for the quarter you are filing.