Last checked Nov 10, 2026
Buying a car in Illinois
The tax you will pay, whether your trade-in lowers it, what the dealer may charge for paperwork, and where to title and register. Taken from official Illinois sources.
- State tax on vehicles
- 6.25%
- Trade-in lowers tax
- Yes
- Doc fee limit
- Limited
- Deadline to title or register
- 20 days
details below
Sales tax on a car in Illinois
Illinois charges a state sales tax of 6.25% on vehicle purchases.
Local taxes are added to the 6.25% state rate and vary by location; for example, the Department of Revenue's vehicle use tax rate for a Cook County address is 7.5% from August 1, 2026, and Chicago adds a 1.25% home rule use tax.
A purchase from a private party is taxed differently, under the Private Party Vehicle Use Tax on Form RUT-50, which uses tax tables, is due within 30 days, and allows no trade-in deduction.
Does a trade-in lower the tax?
On a dealer sale the trade-in credit is subtracted from the selling price before tax. The $10,000 limit on the credit ended for sales on or after January 1, 2022.
Example, state tax only. On a $30,000 car with a $10,000 trade-in, the taxable amount is $20,000, so the state tax is about $1,250. Without the trade-in it would be $1,875. Local taxes and fees are extra.
Dealer doc fees in Illinois
State law sets a base documentary fee of $300 as of January 1, 2020, adjusted each year by the change in the Consumer Price Index. The adjusted maximum for 2026 could not be confirmed from an official source.
The documentation fee is taxed along with the vehicle.
Whatever the rule, the fee is part of your out-the-door price. Ask for it in the written quote and negotiate the total, not the line. See dealer fees explained.
Title and registration
Titles and registrations are handled by the Illinois Secretary of State. The Illinois Vehicle Code requires the buyer to apply for a new title within 20 days after delivery of the vehicle and the assigned title.
Also worth knowing
- Dealers are not required by law to give car buyers a three-day right to cancel.
- The Illinois lemon law covers new vehicles during the first 12 months or 12,000 miles, whichever comes first.
- The taxes, license and title fees, and a documentary service fee may be excluded from a dealer's advertised price.
Sources
- Illinois Department of Revenue: Form ST-556 Instructions (R-12/24) (tax.illinois.gov)
- Illinois Department of Revenue: Form RUT-25 Instructions (R-07/26) (tax.illinois.gov)
- Illinois Department of Revenue: Vehicle Tax FAQs (tax.illinois.gov)
- Illinois General Assembly: Motor Vehicle Retail Installment Sales Act, 815 ILCS 375/11.1 (ilga.gov)
- Illinois General Assembly: Illinois Vehicle Code, 625 ILCS 5/3-112 (ilga.gov)
- Illinois Attorney General: Auto Buying, Financing, and Repair (illinoisattorneygeneral.gov)
- Illinois Attorney General: Buying a New Vehicle (illinoisattorneygeneral.gov)
Last checked Nov 10, 2026; next review by Feb 10, 2027. This page explains how the rules generally work and is not tax or legal advice. Rules change, so confirm with the state. Report an error.
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