Window Tint Laws in California (2026): Legal VLT Limits and Exemptions

California regulates window tint through Cal. Veh. Code §§ 26708, 26708.2, 26708.5. Below: the minimum visible light transmission (VLT) for each window, the windshield rule, what counts as too reflective, who can get a medical exemption, and how an officer checks a car at the roadside.

Legal tint limits in California

• Front side windows: at least 70% VLT.
• Back side windows: any darkness.
• Rear window: any darkness.

VLT is measured through film and glass together. Factory glass already blocks some light, usually landing between 70% and 80% VLT before any film, so a roll sold as "35%" on a window that started at 75% ends up darker than 35% once installed. Officers meter the finished window, not the box the film came in.

Windshield

Transparent, glare-free material that is not red or amber, only above a line 29 inches over the driver's seat (roughly the top 4 to 5 inches).

Federal standard FMVSS 205 sets the baseline for the glass itself: the windshield and front side windows of a new car must transmit at least 70% of visible light. State law decides what film may be added afterwards, which is why the windshield rule is usually a strip above the AS-1 line rather than a percentage.

Reflective and colored film

The windshield strip may not add glare for other drivers; front film must be clear and colorless; medical sun screens are capped at 35% reflectance. Film colors not permitted: red or amber on the windshield; any color on front side window film.

Medical exemptions

California allows darker tint with a medical exemption. A physician/surgeon or optometrist letter allows removable sun screens of at least 35% VLT on the front side windows in daylight only; a dermatologist certificate allows clear UV film on any window.

Stickers, mirrors and enforcement

A certificate or sticker identifying legal tint is required. No sticker, but the installer's (or manufacturer's) certificate for any front side window film must be carried in the vehicle (26708(d)(4)). If the rear window is tinted, the car must have outside mirrors on both sides. Infraction (Cal. Veh. Code 40000.1); normally issued as a correctable equipment citation.

In practice

California's front-window rule effectively rules out tint film: glass plus film must pass 70% light, the film itself must be clear (88% or better) and UV-blocking, and the certificate stays in the car. Windows behind the driver have no limit, and the rear window may be any darkness when both outside mirrors are fitted. The medical exemption does not permit dark film; it allows removable shades on the front side windows in daylight or colorless UV film. Section 26708.5 separately bars installing film that changes glass color or transmittance outside these exceptions.

Sources

• Cal. Veh. Code §§ 26708, 26708.2, 26708.5
• california.public.law
• california.public.law
• california.public.law

Checked Nov 5, 2026. Laws change; confirm with the statute before tinting.