Tint laws by state
Illinois tint laws: the rear windows decide what the front may carry
Illinois ties the front doors to the rear windows. Enter the film on each and the glass: the calculator picks the front limit that the rear allows and checks each window.
Legal in Illinois
35% front side
| Meter reads | Law | Result | |
|---|---|---|---|
| Front side | 35% | 35% | legal |
| Rear side | – | any darkness | any |
| Back window | – | any darkness | any |
Darkest film on this glass: front side 50% · rear side any film · back window any film
Windshield: 6 in.
Illinois ties the front limit to the rear windows: with these rear windows the front side limit is 35%.
The statute does not say how the window is measured; we use film × glass, the reading a meter gives.
Statute: 625 ILCS 5/12-503 · Illinois
Read on an archived copy (web.archive.org) of the official page on ilga.gov, dated June 27, 2026; the official site did not answer automated reading.
Illinois is the one state in this site's data where the darkness of the rear windows sets the limit for the front. Under 625 ILCS 5/12-503, the side windows beside the driver may carry film with 35% light transmittance, with a 5% variance, only if no window behind the driver is below 35%. If the rear windows go down to 30% but no lower, the front doors may carry 50% film. If the rear glass came tinted from the factory, the front limit is also 50%. If any rear window is darker than 30%, the front side windows may not be tinted at all. The rear side windows and the back window have no number of their own, but any car with treated glass behind the driver needs a side mirror on each side. On the windshield, nonreflective film may cover the top 6 inches. Because the text does not say whether the glass counts, the calculator also shows the combined reading: a 35% film on 80% glass reads 28%. A first violation is a petty offense with a fine of $50 to $500.
Darkest legal film for your car
Front side windows · Illinois
43.8%
| Rear side windows | any film |
| Back window | any film |
| Front limit in the law | 35% |
Illinois: the front limit depends on the rear windows (35% if none is below 35%).
Statutes read by Radif Partners · Editorial policy · How the check works
Read on an archived copy (web.archive.org) of the official page on ilga.gov, dated June 27, 2026; the official site did not answer automated reading.
The front limit, step by step
Section 12-503(a-5) does not give one figure for the front side windows. It gives a ladder, and the rear windows decide which rung applies:
| Rear windows | Front side windows may carry | Source |
|---|---|---|
| none below 35% | 35% film, with a 5% variance | 12-503(a-5) |
| none below 30% | 50% film | 12-503(a-5) |
| factory-tinted rear glass | 50% film | 12-503(a-5) |
| any window below 30% | no tint | 12-503(a-5) |
The result surprises many owners: a 20% rear with a 50% front is not legal, because the rear is below 30% and the front must then stay clear. A 30% rear with a 50% front is legal, and so is 35% all around.
Does the glass count?
The Illinois text does not say how the light is measured. Read literally, it speaks of film with a given light transmittance. A meter at the roadside reads the window as it is, film and glass together:
| Film | Combined on 75% glass | Combined on 85% glass |
|---|---|---|
| 50% | 37.5% | 42.5% |
| 35% | 26.2% | 29.8% |
| 30% | 22.5% | 25.5% |
The calculator above marks a 35% film as legal on the film itself and shows the combined figure beside it, so you can see how far from the 30% floor of the variance a meter would place you. Here is the darkest film for each window type on your glass:
Darkest legal film for your car
Front side windows · Illinois
43.8%
| Rear side windows | any film |
| Back window | any film |
| Front limit in the law | 35% |
Illinois: the front limit depends on the rear windows (35% if none is below 35%).
Mirrors, windshield and reflection
Any vehicle with a treated window behind the driver's seat must have a side mirror on each side. On the windshield, only nonreflective tinted film on the uppermost 6 inches is allowed, and front film must be nonreflective too.
Medical exemption
A certified statement from an Illinois-licensed physician exempts the vehicle from the windshield and front side window rules. The statute lists examples such as lupus, porokeratosis, light sensitivity after a brain injury and albinism. The statement is renewed every 4 years, a copy goes to the Secretary of State and the vehicle needs distinctive plates or stickers.
Penalty and the court order
A first violation is a petty offense, punished by a fine of $50 to $500. A second or later violation becomes a Class C misdemeanor, with a fine of $100 to $500. In both cases the court orders the windows brought into compliance, so paying the fine does not end the matter: the film has to come off or be replaced, and a car bought from another state with darker front film has to be brought to the Illinois ladder before it is driven here.
Around Illinois
Wisconsin asks for 50% on the front doors and 35% behind, Iowa 70% on the front, Missouri 35%, Kentucky 35% and Indiana 30%. Read on an archived copy (web.archive.org) of the official page on ilga.gov, dated June 27, 2026; the official site did not answer automated reading.