Under California window tint law, the front windshield and the two front side windows have to stay essentially clear: no darkening film is allowed on the front side windows, and the windshield can only carry a transparent strip across the very top. Everything behind the driver — the rear side windows and the back glass — can be tinted as dark as you want, provided the car has working outside mirrors on both sides. That split between “front” and “rear” is the whole framework, and it’s stricter than what most other states allow up front.
Front Side Windows Are the Rule That Trips People Up
This is where drivers coming from other states get caught. California prohibits any material on the front side windows that “alters the color or reduces the light transmittance” of the glass.1California Legislative Information. California Code Vehicle Code 26708.5 A traditional aftermarket tint film — even a light one — is not legal on the driver’s window or the front passenger window.
The only aftermarket product you can put on those windows is a clear, colorless, transparent UV-blocking film. That film has to let at least 88% of visible light through on its own, and the combined glass-plus-film has to meet the federal safety standard (FMVSS 205), which requires at least 70% light transmittance. The installer has to give you a certificate confirming the material meets those specs, and you should keep it in the vehicle.2California Legislative Information. California Code Vehicle Code 26708
People sometimes hear “70% VLT” and assume California allows a 70% film on the front windows. It doesn’t. That 70% figure comes from the federal floor for factory-installed tinted safety glass, which is allowed because it’s built into the glass itself.1California Legislative Information. California Code Vehicle Code 26708.5 A slight greenish or grayish factory tint on a new car is fine. Adding a 70% film over that factory glass is not, unless the film meets the clear, colorless, UV-only criteria above.
The Windshield: A Strip at the Top, Nothing More
California law bans placing anything on the windshield that obstructs or reduces the driver’s view. The single exception is a transparent strip across the top of the glass, meant to cut sun glare. The statute defines the allowed area using a seat-based measurement rather than a flat inch count from the top: the bottom edge of the material has to sit at least 29 inches above the lowest point of the driver’s seat. On most cars that works out to roughly the top four or five inches of glass, but it varies by vehicle.2California Legislative Information. California Code Vehicle Code 26708
The strip material itself has limits. It can’t be red or amber, it can’t carry opaque lettering, and it can’t reflect sunlight or headlights into other drivers’ eyes any more than plain glass would.2California Legislative Information. California Code Vehicle Code 26708 Blue isn’t listed by name, but a film that distorts vision or alters primary colors is also prohibited, and that catch-all can pick up strong-colored films during enforcement. Highly mirrored or chrome-style films are effectively out too.
Rear Side Windows and the Back Glass
Behind the driver, the rules loosen up completely. Side windows to the rear of the driver are fully exempt from the tint restrictions, so limo-dark film is legal there.2California Legislative Information. California Code Vehicle Code 26708
The back window can also go any darkness, but only if the vehicle has outside mirrors on both the left and right sides, positioned so the driver can see at least 200 feet behind the vehicle through each one.2California Legislative Information. California Code Vehicle Code 26708 Nearly every modern car and SUV already has dual mirrors, so this rarely comes up. On an older or modified vehicle with a single mirror, tinting the back glass would put you out of compliance.
Medical Exemptions
Two separate medical exemptions exist, and they cover different situations.
Clear UV Film for Skin or Photosensitivity Conditions
A person with a medical condition that requires protection from ultraviolet rays, such as lupus or severe photosensitivity, can have clear, colorless, transparent UV-blocking film applied to the windshield, side windows, or rear windows. The film still has to meet the 88% film transmittance and 70% combined transmittance standards, so it won’t look darker than untreated glass. The driver has to carry a certificate signed by a licensed dermatologist stating the medical need. If the film tears, bubbles, or deteriorates enough to obstruct clear vision, it has to be removed or replaced.2California Legislative Information. California Code Vehicle Code 26708
Removable Sun Screening Devices
A separate exemption allows removable sun screening devices on the front side windows for a medical or visual condition. The driver or front-seat passenger has to carry a signed letter from a licensed physician (medical condition) or licensed optometrist (visual condition). The devices are limited to green, gray, or neutral smoke colors with at least 35% light transmittance, or louvered designs where at least 35% of the surface is open, and they can’t exceed 35% reflectivity. They can’t be used at night.3California Legislative Information. California Code Vehicle Code 26708.2
What Happens If You Get Caught
A tint violation in California is usually written as a correctable offense, the familiar “fix-it ticket.” You remove the illegal tint, take the vehicle to a law enforcement officer to verify the correction, get the ticket signed off, and submit proof to the court along with a $25 fee per violation.4California Legislative Information. California Code Vehicle Code 40611
Ignoring the ticket is where it gets expensive. Failing to correct the violation or missing the court deadline can convert the matter into a standard infraction with fines climbing toward $200 for a second offense, along with additional court fees and, in some cases, a hold on your vehicle registration.
There’s an insurance wrinkle too. If you’re in an accident and your windows carry illegal tint, your insurer may decline to cover damage to those windows, especially if the tint was an undisclosed modification.
Commercial Vehicles Follow a Different Standard
If you drive a commercial motor vehicle, federal rules from FMCSA apply on top of California law. The windshield and the windows immediately to the driver’s left and right have to maintain at least 70% light transmittance; the rule does not reach windows elsewhere on the vehicle.5FMCSA. May Windshields and Side Windows Be Tinted? The federal standard also requires the windshield to stay free of discoloration or damage in the driver’s primary viewing area.6eCFR. 49 CFR 393.60 – Glazing in Specified Openings
Tint and Driver-Assist Cameras
Newer vehicles use forward-facing cameras behind the windshield for lane-keeping assist, automatic emergency braking, and traffic sign recognition. Those cameras need a clean, consistent view. Well-installed clear film usually doesn’t interfere, but poor installation — bubbles, haze, or distortion in the camera’s field of view — can cause malfunctions or delayed warnings. If your car has any Advanced Driver Assistance Systems, check with the manufacturer before applying anything to the windshield, even within the legally permitted strip. A film that passes the Vehicle Code can still cause practical trouble if it sits in front of a camera sensor.