Washington Window Tint Law
What the statute actually says, in plain language, with the part almost everyone gets wrong.
The short answer
On any window except the windshield, film must let through at least 24% of light and reflect no more than 35%, on a vehicle with outside mirrors on both sides. Trucks, motor homes and multipurpose passenger vehicles may go darker than 24% behind the driver. Windshields get a six inch transparent strip at the top. Everything here is from RCW 46.37.430.
The mistake almost everyone makes
Search for Washington tint limits and you will repeatedly see "35% is the legal limit." That is wrong, and it is wrong in a way that costs people money.
The statute contains two separate numbers:
- 24% light transmission (VLT) — the minimum amount of light that must pass through. This is the darkness limit.
- 35% reflectance — the maximum amount of light the film may bounce back. This is the mirror limit.
They get collapsed into one number by people repeating each other. The practical consequence: drivers who believe 35% is the legal floor turn down 24% film that is entirely legal, and lose a meaningful amount of heat rejection for no reason.
Worth being precise about: the 24% figure is net film screening — the combined result of the factory glass and the film you add. Your windows are already tinted from the factory, usually somewhere in the 70–80% range. That existing tint counts toward the total.
What the statute allows, by window
| Window | What is allowed |
|---|---|
| Front side windows | 24% VLT or more, 35% reflectance or less, with mirrors both sides |
| Rear side windows — normal car | Same: 24% VLT or more |
| Rear side windows — truck, motor home or MPV | May go below 24% VLT, if reflectance stays at or below 35% and both outside mirrors are fitted |
| Rear windscreen | Follows the same rule as the side windows for that vehicle class; both outside mirrors required |
| Windshield | Transparent film along the top edge only, not extending into the AS-1 area or more than six inches down. Clear UV film is permitted across the whole windshield. |
The truck and SUV exception, properly explained
This is the most valuable thing on this page and almost no shop explains it.
The statute lists vehicle classes that may have film below 24% VLT on any window to the rear of the driver: hearses, collector vehicles, limousines, passenger buses used for compensation, ambulances, rescue and emergency medical vehicles — and, critically, any vehicle identified by the manufacturer as a truck, motor home, or multipurpose passenger vehicle as defined in 49 CFR 571.3.
"Multipurpose passenger vehicle" is a federal classification, and it covers a very large share of what people call SUVs and crossovers. If your vehicle is classified that way by its manufacturer, you can legally run genuinely dark film in the back while keeping the front doors legal.
Two conditions still apply: reflectance at or below 35%, and outside mirrors on both sides.
How to check your vehicle's class: it is on the manufacturer's certification label, usually on the driver's door jamb. It will say "TRUCK", "MPV", "PASSENGER CAR" or similar. Tell us what yours says and we will tell you what you can legally run.
Film that is illegal regardless of darkness
- Mirror finish products — prohibited outright
- Red, gold, yellow or black film — named specifically in the statute
- Liquid tint sprayed or brushed on — prohibited
- More than one sheet of film on a window — stacking film to get darker is not allowed
Mirrors
The mirror requirement runs through the whole statute. When film is applied to any window other than the windshield, the outside mirrors on both left and right must give the driver a view of at least 200 feet to the rear. If a vehicle is missing a mirror, the darker allowances stop applying.
Medical exemption
The statute permits a greater degree of light reduction on all windows and the top six inches of the windshield where the driver or a passenger carries written verification from a licensed physician that they must be protected from sunlight for physical or medical reasons. Conditions like lupus and certain photosensitivity disorders are the usual reason. Carry the documentation in the vehicle.
What happens if the film is not compliant
The statute makes it a traffic infraction to operate a vehicle on Washington roads with film that violates the section. Beyond the ticket, non-compliant film usually has to come off, which means paying twice.
How we handle this
We will tell you what your specific vehicle is allowed before anything goes on the glass, including whether it qualifies for the truck and MPV allowance. If you ask for something that is not legal, we will say so and explain the alternative rather than fitting it and letting you find out from an officer.
Questions we get
What is the legal tint limit in Washington?
On side and rear windows, film must let at least 24 percent of light through and reflect no more than 35 percent, on a vehicle with outside mirrors on both sides. Trucks, motor homes and multipurpose passenger vehicles are allowed darker film behind the driver.
Is 35% tint legal in Washington?
Yes, comfortably. 35 percent VLT is well above the 24 percent minimum. The 35 percent figure in the statute is the reflectance limit, not the darkness limit - those are two different numbers that get confused constantly.
Can I tint my windshield?
Only the top six inches, and the film must be transparent and must not extend into the AS-1 area. Clear film that blocks UV without reducing light is allowed across the whole windshield.
Is limo tint legal in Washington?
Not on a normal car. On a truck, motor home or multipurpose passenger vehicle it can be legal behind the driver, provided reflectance stays at or below 35 percent and the vehicle has both outside mirrors.
What tint is illegal in Washington?
Mirror-finish film, and any film that is red, gold, yellow or black. Liquid tint that is sprayed or brushed on is also prohibited. Stacking more than one sheet of film on a window is not allowed.
What happens if my tint is too dark?
Operating a vehicle with non-compliant film is a traffic infraction under the statute.
Can I get a medical exemption?
The statute allows a greater degree of light reduction on all windows and the top six inches of the windshield for a driver or passenger who carries written verification from a licensed physician that they must be protected from sunlight.
This page summarises RCW 46.37.430 as we read it. It is a summary written by a tint installer, not legal advice, and the statute is the authority. Read it yourself — it is short.