Not legal advice. This guide summarizes the California Vehicle Code (CVC) as of September 30, 2026. Laws change, and how they’re enforced can vary. Check the current statute or ask an attorney if you need a definitive answer.
Hot afternoons on the 55 make tint tempting. But California’s tint rules are strict, and much of what you hear about them is wrong. Here’s what the law says, window by window, with statute sections you can check yourself.
The short version
Window | What California allows |
|---|---|
Windshield | A strip at the top, above a line 29 inches over the driver’s seat. Clear film on the full windshield only with a dermatologist’s certificate. (CVC §26708(c), §26708(e)) |
Front side windows | Only clear, colorless film of at least 88% VLT. The window with film must still pass 70%. The installer provides a certificate. (CVC §26708(d)) |
Rear side windows | Film of any darkness (CVC §26708(b)(4)) |
Rear window | Film of any darkness, if the car has outside mirrors on both sides (CVC §26708(b)(8)) |
VLT means visible light transmission, the percentage of visible light that passes through. A lower number means a darker window.
Where the rules come from
California starts with a broad ban. CVC §26708(a)(1) says a person shall not drive a vehicle “with any object or material placed, displayed, installed, affixed, or applied upon the windshield or side or rear windows.” Everything that’s allowed is an exception to that rule.
A second section, CVC §26708.5(a), bans transparent material that “alters the color or reduces the light transmittance” of the windows, except as §26708 allows. Glass that comes tinted from the factory is fine as long as it meets federal safety glazing standards (§26708.5(b)).
The windshield
The sun strip
You can add transparent material to “the topmost portion of the windshield” under §26708(c) if all four conditions are met:
The bottom edge is at least 29 inches above the undepressed driver’s seat. It’s measured from a point 5 inches in front of the bottom of the backrest, with the seat all the way back and down and the car on level ground.
It isn’t red or amber.
It has no opaque lettering, and any other lettering doesn’t affect primary colors or distort vision.
It doesn’t reflect sunlight or headlight glare into other drivers’ eyes any more than the windshield itself does.
You may hear “the top 4 inches” or “down to the AS-1 line.” Neither phrase appears in the California statute. The 29-inch measurement is what counts.
Clear film on the full windshield
Since January 1, 2018, §26708(e) has allowed clear, colorless, transparent film on the windshield, side and rear windows, but only when every condition is met. The film must have at least 88% VLT. The glass with film applied must still meet federal standard FMVSS 205, including 70% light transmittance. The film must be designed to help block UVA rays. And the driver must carry “a certificate signed by a licensed dermatologist” stating the person shouldn’t be exposed to UV because of a medical condition.
Without that certificate, film on the windshield below the sun strip isn’t allowed, however clear it is.
Front side windows
This is where most tickets happen. Under §26708(d), the only film allowed on the windows next to the driver and front passenger is “clear, colorless, and transparent material,” and only if:
The film has a minimum VLT of 88%.
The glass with film applied meets FMVSS 205, including 70% minimum light transmittance.
The film is designed to help the glass block UVA rays.
The driver keeps a certificate in the car, signed by the installing company. It must name the installer and the film manufacturer, with their full names and street addresses.
The film is removed or replaced if it tears, bubbles or wears enough to block clear vision.
The “70% tint” myth
You’ll often hear that “70% tint is legal in California.” That isn’t what the law says. The film itself has to be clear and at least 88% VLT. Then the window as a whole, glass plus film, has to pass 70%.
The numbers multiply. Federal rules already require front side glass to pass at least 70%, and factory glass often isn’t far above that. A film rated at 70% VLT on glass that passes 75% leaves about 52% (0.70 × 0.75). That fails.
Rear side windows and the rear window
California is relaxed behind the driver. Side windows “to the rear of the driver” are exempt under §26708(b)(4), with no darkness limit in the statute.
The rear window is exempt under §26708(b)(8) if the car has outside mirrors on both the left and right sides that give the driver a view at least 200 feet to the rear. Most cars come with both mirrors, but if one is missing or broken, a tinted rear window becomes a problem.
No limit doesn’t mean darker is always better. Very dark rear glass can make reversing at night harder. Pick a shade you’re comfortable driving with after dark.
Medical exemptions
There are two separate medical provisions, and neither one allows permanent dark film on the front side windows.
Removable sun screens
Under §26708(b)(10), you can use sun screening devices on the front side windows if the driver or a front passenger carries a letter from a licensed physician and surgeon (for a medical condition) or a licensed optometrist (for a visual condition). The devices must meet §26708.2:
They must be removable, held by a frame, temporary fasteners or a roller shade.
Transparent devices must be green, gray or neutral smoke, with at least 35% luminous transmittance.
They can’t be more than 35% reflective on either side.
They “shall not be used during darkness.”
Clear film with a dermatologist’s certificate
This is the §26708(e) exemption covered above. It allows clear film of at least 88% VLT on any window, including the windshield. It doesn’t allow tinted film.
Tickets and fix-its
A tint violation is an equipment infraction. For most equipment infractions, CVC §40303.5(e) says the officer must allow you to sign a notice to correct the violation, often called a fix-it ticket, unless a disqualifying condition applies. You then remove or replace the film and get proof of correction. Fees and court procedures vary, so read your citation carefully.
How to get heat rejection without going darker
Here’s the part most people miss: darkness and heat rejection are not the same thing. Much of the sun’s heat arrives as infrared light, which you can’t see. Ceramic and multilayer films are designed to block infrared while letting more visible light through.
3M’s data shows how much infrared even a light shade can reject:
3M Crystalline Black CR BLK 70: 64% VLT and 97% infrared rejection (900–1,000 nm), per 3M data on automotive glass.
Specs vary by shade and by how they’re measured, so compare shades within a film line.
One important caveat: a light ceramic shade like this is not the clear, 88% VLT film California requires on the front side windows. It’s a good option for the rear side windows and rear window if you want heat rejection with a lighter look and better night visibility. For the front side windows and the windshield, the clear-film rules above apply.
How we handle it
At Cyber Tint & PPF, we go over California’s rules for each window before you choose a film and coverage. Our window tint page lists the specs for every film line we install. Questions? Call or text 626‑782‑1822, or request a quote.
FAQ
Is 5% tint legal in California?
On the rear side windows, yes, because California sets no darkness limit there. On the rear window, yes, if the car has outside mirrors on both sides. On the front side windows and the windshield, no.
What’s the darkest legal tint for front windows in California?
There’s no legal tint percentage for the front side windows. Only clear, colorless film of at least 88% VLT is allowed, and the window must still pass 70% with the film applied (CVC §26708(d)).
Can a medical exemption let me tint my front windows dark?
Not with permanent film. A physician’s or optometrist’s letter allows removable sun screens of at least 35% transmittance, and they can’t be used after dark. A dermatologist’s certificate allows clear film only (CVC §26708(b)(10), §26708.2, §26708(e)).
Is clear film on the windshield legal?
On the full windshield, only with a licensed dermatologist’s certificate under CVC §26708(e). Without one, film is limited to the strip at the top, above the 29-inch line in §26708(c).
Do I need a certificate for front window film?
Yes. For clear film on the front side windows, the driver must keep a certificate from the installing company in the car (CVC §26708(d)(4)).
Sources
Written by Cyber Tint & PPF
Window tint, paint protection film, vinyl wraps and ceramic coating in Santa Ana, CA. 3M Pro Shop Dealer.
