What the law actually says.

California's front-side-window rule is more specific than simply choosing “70% tint.” Under Vehicle Code §26708(d), qualifying clear material must itself have at least 88% visible-light transmission, and the finished glass-and-film combination must still satisfy the applicable 70% federal glazing requirement under FMVSS 205.

Those are two separate tests, and both have to be met. A film sold as “70%” clears neither of them on its own: it falls well short of the 88% threshold the statute sets for the material, and it says nothing about what the glass reads once the film is applied.

Factory glass already affects total VLT, so legality cannot be determined from the film label alone. Two cars with the same film can measure differently because their glass is different.

The statute also attaches other conditions to this exception, including required certification documentation. Those conditions are part of the rule, not optional paperwork.

Side windows behind the driver are treated differently from front side windows, and they are not subject to the same front-window restrictions.

That is not the same as “anything goes behind the driver.” Where rear glazing is tinted, the statute brings in additional conditions — including mirror requirements, so the vehicle retains adequate rearward visibility.

We confirm what applies to your specific vehicle and glass layout before installing anything.

California permits qualifying transparent material on the topmost portion of the windshield, but the legal boundary is defined by a statutory seat-position measurement rather than a universal four-inch strip.

Under §26708(c), the bottom edge of that material must sit at least 29 inches above the undepressed driver's seat, measured the way the statute describes. Because seat height and windshield rake differ between vehicles, the resulting strip is not the same size on every car.

The statute additionally restricts color, lettering, and reflectivity for material in this area.

California provides specific medical provisions that can allow tinting which would otherwise be restricted. These require appropriate documentation and carry their own statutory conditions.

We are not able to advise on whether a specific individual qualifies. If you think a medical exemption may apply to you, review the current statute and speak with the appropriate medical and legal professionals.