Massachusetts Window Tint Law 2026

The exception (4) 35% figures are scoped to the side windows and the rear window and do not reach the windshield. Because exception (5) is limited to TRANSPARENT material, a darkness percentage for the Massachusetts windshield strip would be a category error rather than merely a missing number.

Massachusetts uses neither the AS-1 line nor a whichever-is-closer tie-breaker: a flat 6 inches from the top, subject to a second condition that the strip not encroach on the driver's direct forward viewing area as defined by the FMVSS. Critically the permitted material must be TRANSPARENT — this is not an allowance for a tinted band, which is what the AS-1 states grant. Illinois (6") is the only other flat-inch state observed; Michigan writes 4".

THE FRONT ALLOWANCE IS MIRROR-CONDITIONED — unique among the states extracted so far. M.G.L. c.90 §9D exception (4) grants the 35% allowance only "if the vehicle is equipped with two outside mirrors, one on each side, adjusted so that the driver has a clear view of the highway behind the vehicle." The mirrors are a condition precedent to the allowance, not an independent duty — without them the flat prohibition in the body of §9D governs. FILM basis: the subject of "which has a total visible light reflectance ... or a visible light transmittance" is the "nontransparent or sunscreen material or window application", not the window. CONJUNCTION RECORDED AS WRITTEN: the statute says reflectance "not more than thirty-five per cent OR a visible light transmittance of not less than thirty-five per cent". A literal disjunctive reading would permit a film that meets one figure and fails the other, which is almost certainly not the intent; a conjunctive reading is how the two figures are conventionally applied. This dataset does not resolve the ambiguity — it carries both figures as separate rows with the quote intact so a reader sees the actual text. Resolving it would require the registrar's regulations issued under the §9D rulemaking clause, which were not retrieved.

Massachusetts does not step down behind the driver — the same 35% figure governs the front side windows, the side windows immediately to the rear, and the rear window, all under the same mirror condition. M.G.L. c.90 §9D exception (4) grants the 35% allowance only "if the vehicle is equipped with two outside mirrors, one on each side, adjusted so that the driver has a clear view of the highway behind the vehicle." The mirrors are a condition precedent to the allowance, not an independent duty — without them the flat prohibition in the body of §9D governs.

Carried because the taxicab exclusion is the kind of detail that gets lost in summarization and inverts the answer for a whole vehicle class. Unlike exception (4), this carve-out is NOT conditioned on two outside mirrors and is not limited by any percentage — it is a full exemption for behind-the-driver glass on qualifying livery vehicles. Note it reaches only vehicles actually "hired for that purpose", so it is use-dependent rather than purely registration-dependent.

M.G.L. c.90 §9D exception (4) grants the 35% allowance only "if the vehicle is equipped with two outside mirrors, one on each side, adjusted so that the driver has a clear view of the highway behind the vehicle." The mirrors are a condition precedent to the allowance, not an independent duty — without them the flat prohibition in the body of §9D governs. Exception (2) provides a separate, parallel route for the rear window and the side windows to the rear of the driver: "the use of draperies, louvers, or other special window treatments, except those specifically designated in this section", on the same two-mirror condition. So Massachusetts treats physical window treatments and film under different exceptions with the same mirror precondition.

Massachusetts sets the reflectance ceiling and the transmittance floor at the same figure, 35% — different quantities sharing a number, as in Nebraska. CONJUNCTION RECORDED AS WRITTEN: the statute says reflectance "not more than thirty-five per cent OR a visible light transmittance of not less than thirty-five per cent". A literal disjunctive reading would permit a film that meets one figure and fails the other, which is almost certainly not the intent; a conjunctive reading is how the two figures are conventionally applied. This dataset does not resolve the ambiguity — it carries both figures as separate rows with the quote intact so a reader sees the actual text. Resolving it would require the registrar's regulations issued under the §9D rulemaking clause, which were not retrieved.

Exception (4) states one reflectance ceiling covering the front side windows, the side windows immediately to the rear and the rear window alike, on the two-mirror condition. Note that the body of §9D independently bars "reflective film" that makes a window "in any way nontransparent or obscured", so the 35% figure operates as a safe harbour from that prohibition rather than as a freestanding cap.

The most institutionally heavyweight medical route observed so far: a written application to the MEDICAL ADVISORY BOARD established under c.90 §8C, supported by a written attestation from a physician licensed in Massachusetts, granted by the board, after which the REGISTRAR issues a sticker affixed to the side window immediately adjacent to the operator, and the registrar keeps a central record of every sticker issued. Contrast West Virginia and Minnesota, where a carried physician document suffices with no agency in the loop. The exemption is limited to a PRIVATE PASSENGER motor vehicle and to an owner or operator "determined to be light or photosensitive".

Recorded as a VERIFIED "no general label duty" rather than a gap, because §9D affirmatively sets out its own compliance-proof mechanism and it is not a label: the registrar tests glazing and issues an attestation that carries evidentiary weight. The registrar is directed to "establish rules and regulations to provide standards to measure the aforementioned percentage of reflectance and transmittance of light, and shall provide for testing of any motor vehicle glazing alleged to be in violation". Those regulations were not retrieved and could impose a labelling duty; none appears in the statute. Contrast Minnesota, where an unmarked film makes the vehicle unlawful to drive.

True, but broader than the dimension name suggests, and the dataset should render it that way: in Massachusetts the two-mirror condition gates ALL aftermarket tint on side and rear glass — including the driver's own window — not merely tint behind the driver. Maine attaches the same condition only to the behind-the-operator exemption. Exceptions (2) and (3) repeat the identical mirror formula, so it is the section's general precondition for departing from full transparency.