Did you know that more than 60 % of Montana drivers have some level of window tint even though the state enforces strict light‑transmission limits? The short answer is that tint is legal in Montana, but only when it complies with the state’s VLT (visible light transmission) percentages and the new 2026 amendments. Drivers must keep front‑side windows at least 70 % VLT, while rear and side‑back windows may be as dark as 35 % VLT, provided the vehicle has side mirrors that meet the required field‑of‑view standards. Failure to meet these thresholds can result in fines, vehicle inspection holds, and mandatory removal of the tint.
Current Legal Status
Montana’s vehicle code (Mont. Code Ann. § 61‑6‑202) permits tinted glass on passenger vehicles, but it sets explicit VLT limits. Front side windows must allow 70 % or more of visible light, while back side and rear windows may drop to 35 % VLT. The law also requires that any tint on the rear side windows be accompanied by side mirrors that provide a clear view of at least 200 feet behind the vehicle. These requirements have been in effect since 2014 and apply to both new and used vehicles.
2026 Rule Changes
Effective January 1, 2026, Montana amended its tint regulations in three key ways:
- Medical Exemptions: Drivers with documented photophobia may obtain a court‑issued exemption allowing front‑side tint down to 50 % VLT, provided a permanent medical record is attached to the vehicle registration.
- Reflective Coatings: Metallic or mirrored finishes that exceed a 20 % reflectance rating are now prohibited on any window, aiming to reduce glare for law‑enforcement cameras.
- Inspection Enforcement: The state will conduct random spot‑checks at DMV renewal stations. Non‑compliant tint will trigger a $250 civil citation and a mandatory re‑tint before the registration can be renewed.
These updates were adopted after a 2025 legislative study showed a 12 % rise in accidents involving glare from overly reflective films.
Penalties and Enforcement
Violations are handled as civil infractions. First‑time offenders typically receive a $250 fine and a written notice to correct the tint within 30 days. Subsequent offenses can double the fine and may result in a hold on vehicle registration until the tint is removed or replaced. Law‑enforcement officers may also issue a “stop‑and‑inspect” order if they suspect the tint violates the VLT limits, and the vehicle can be impounded until compliance is verified.
How to Verify Compliance
Most automotive tint shops use a handheld photometer that measures VLT to two decimal places. Montana requires a certification sticker on the inside of each tinted window, indicating the measured VLT and the date of installation. Keep this sticker accessible; it serves as primary evidence during any inspection.
FAQs
What VLT percentage is allowed on the front windshield?
The front windshield must have a VLT of at least 70 %, meaning no tint film may be applied that reduces light transmission below that level. Sun‑roof panels are exempt, provided they meet the same VLT requirement.
Can I use a non‑metallic reflective film on the rear windows?
No. Beginning in 2026, any reflective coating that exceeds a 20 % reflectance rating is prohibited on all windows, including rear and side‑back panels. The law targets both safety and law‑enforcement imaging concerns.
How do I obtain a medical exemption for darker front‑side tint?
You must obtain a written diagnosis from a licensed physician confirming photophobia or a related condition, file a petition with the Montana District Court, and receive a written exemption order. The order is then attached to your vehicle registration and permits front‑side tint down to 50 % VLT.
Will a tint that is slightly darker than the legal limit result in a fine?
Yes. Even a 1 % deviation is considered non‑compliant and can trigger the standard $250 civil citation. The vehicle must be re‑tinted to meet the legal VLT before the fine can be dismissed.
Are aftermarket tint kits legal for do‑it‑yourself installations?
They are legal only if the resulting VLT complies with the statutory limits and the installation includes the required certification sticker. DIY installers should have the windows measured with a calibrated photometer and retain documentation in case of a future inspection.