California window tint: no darkening film on front side windows

The governing text is Vehicle Code section 26708(a)(1), which says a person "shall not drive any motor vehicle with any object or material placed, displayed, installed, affixed, or applied upon the windshield or side or rear windows." Paragraph (a)(2) adds anything placed anywhere in the vehicle that obstructs or reduces the driver clear view through the windshield or side windows, and paragraph (a)(3) applies the same rule to snow and ice. Section 26708.5(a) closes the loop from the installer side: no one may place, install, affix or apply transparent material on the windshield or side or rear windows if it alters the color or reduces light transmittance, except as subdivisions (b), (c) or (d) of section 26708 allow. Worth noting that section 26708.5(a) still names only subdivisions (b), (c) and (d); the Legislature added a new subdivision (e) to section 26708 by Stats. 2025, Ch. 417, Sec. 5, effective January 1, 2026, without updating that cross reference.

For the two windows next to the front seat, subdivision (d) is the only opening. The material must be clear, colorless and transparent, must have a minimum visible light transmittance of 88 percent, and the window glazing with the material applied must meet all of FMVSS No. 205 (49 C.F.R. 571.205), including the 70 percent minimum light transmittance and the abrasion resistance of AS-14 glazing. The film has to be designed and manufactured to enhance the glass ability to block ultraviolet A rays. The driver must keep, in hand or in the vehicle, a certificate signed by the installing company that identifies both the installing company and the material manufacturer by full name and street address; an owner who installs the film personally must instead carry a manufacturer certificate. If the film tears, bubbles, or is otherwise worn to prohibit clear vision, subdivision (d)(5) requires it to be removed or replaced.

The windshield allowance is subdivision (c), and it is measured, not eyeballed. Transparent material may go on the topmost portion only if the bottom edge sits at least 29 inches above the undepressed driver seat, measured from a point five inches in front of the bottom of the backrest with the seat in its rearmost and lowermost position and the vehicle on a level surface. The strip may not be red or amber, may carry no opaque lettering, and any other lettering must not affect primary colors or distort vision through the glass. It also may not reflect sunlight or headlight glare into the eyes of occupants of oncoming or following vehicles any more than the bare windshield would.

Behind the driver the code steps back almost entirely. Section 26708(b)(4) exempts "side windows that are to the rear of the driver" from subdivision (a), so rear door and quarter glass carry no transmittance figure. Section 26708(b)(8) exempts the rear window or windows, but only where the vehicle carries outside mirrors on both the left and right sides positioned to reflect to the driver a view of the highway for at least 200 feet to the rear through each mirror. A blacked-out back window on a car missing a side mirror is therefore not covered by that exemption.

A tint violation is an infraction. Under Vehicle Code section 42001(a) the fine may not exceed $100 for a first infraction, $200 for a second within one year of a conviction, and $250 for a third or subsequent within a year of two or more convictions, before penalty assessments. 5(e) directs the arresting officer to let the driver sign a promise to correct under section 40610, and section 40610(a)(1) makes that notice mandatory unless the officer finds one of the section 40610(b) disqualifiers: evidence of fraud or persistent neglect, an immediate safety hazard, or a driver who will not or cannot promptly correct the problem.

The notice must state a reasonable correction time not exceeding 30 days. Proof of correction may be certified by a police department, the California Highway Patrol, a sheriff, a marshal, or any other agency regularly engaged in Vehicle Code enforcement under section 40616(c), and on proof the clerk collects a $25 transaction fee for each violation under section 40611(a). Willfully violating the written promise or failing to deliver proof is a misdemeanor under section 40616, and section 40618 lets the issuing agency send the unfulfilled promise to court, where it becomes the complaint.

The section 40610 now in force is itself repealed as of January 1, 2027 in favor of a later version added by Stats. 2022, Ch. 595, Sec. 5.