Montana Windshield Mounting Laws (2026 Guide)

Montana bans mounting GPS devices, phones, and dashcams on the windshield. Under MCA 61-9-405, drivers may not attach any nontransparent material that materially obstructs their view of the road. Dashboard mounts, vent clips, and console mounts are the legally safe alternatives for device placement in Montana.

Montana takes a strict approach to windshield visibility. Under Montana Code Annotated (MCA) Section 61-9-405, drivers are prohibited from placing any nontransparent material on the windshield that materially obstructs their view of the road. This statute applies broadly to GPS devices, phone holders, dashcams, and any other object that could interfere with the driver's line of sight through the windshield.

Understanding this law is important for anyone driving in Montana, whether you are a resident, a commercial driver, or a visitor passing through the state. The penalties for violations are real, and law enforcement can cite drivers during routine traffic stops.

What the Law Actually Says

MCA 61-9-405 is titled "Windshields required, exception -- unobstructed and equipped with wipers -- window tinting and sunscreening -- restrictions -- exemptions -- definitions." The statute covers several areas, but the section most relevant to windshield-mounted devices is subsection (2)(a).

Subsection (2)(a): The Obstruction Prohibition

A person may not drive a motor vehicle with "a sign, poster, substance, or other nontransparent material upon the front windshield, side wings, or side or rear windows of the vehicle that materially obstructs, obscures, or impairs the driver's clear view of the highway or an intersecting highway."

The critical phrase is "nontransparent material." Any device mounted to the windshield, whether it is a GPS unit, a phone cradle, a dashcam, or a toll transponder, qualifies as nontransparent material. The legal question then becomes whether that device "materially obstructs" the driver's view.

Subsection (2)(b): Defective Windshields

The statute also prohibits driving with "a windshield that is shattered or in such a defective condition that it materially impairs or obstructs the driver's clear view." Cracks, chips, and other damage that compromise visibility are treated as separate violations under the same section.

Subsection (1): Windshield Requirement

Every motor vehicle in Montana must be equipped with a front windshield that meets the standards set in MCA 61-9-408. Motorcycles, quadricycles, motor-driven cycles, and farm tractors are excepted from that requirement outright, and all four classes are treated identically by the statute. The trailing clause about eye protection is a separate alternative open to motor vehicles generally: a vehicle need not carry a conforming windshield if the driver wears safety glasses, goggles, or face shields at all times during operation. It is not a condition attached to the four excepted classes.

Subsection (3): Windshield Wipers

All motor vehicles with windshields must be equipped with a functioning device for clearing rain, snow, or other moisture. Given Montana's harsh winter conditions, this requirement carries practical significance beyond legal compliance.

GPS and Phone Mounts

Montana does not carve out a specific exception for GPS devices or phone holders mounted to the windshield. Unlike some states that allow devices within a defined zone (such as the lower corner of the windshield), Montana applies its "materially obstructs" standard broadly.

A suction cup GPS mount attached to the windshield is considered nontransparent material under the statute. If an officer determines that the device obstructs your clear view of the highway, you can be cited. The same applies to phone cradles, tablet mounts, and any other device attached to the windshield glass.

Legal Alternatives for Device Mounting

Because windshield mounting is restricted, Montana drivers should consider these alternatives:

• Dashboard mounts: Adhesive or friction-based mounts that sit on top of the dashboard keep your device visible without touching the windshield glass.
• Vent-clip mounts: These attach to the vehicle's air vents and hold a phone or small GPS at eye-friendly height.
• Console mounts: Cup holder mounts and center console mounts keep devices accessible without any windshield contact.
• Adhesive disc adapters: A 3M adhesive disc placed on the dashboard allows you to use a suction cup mount on the dash surface rather than the windshield.

The key principle is keeping the windshield completely clear of any mounted objects while still having access to navigation and communication tools.

Dashcam Rules in Montana

Montana does not have a specific statute addressing dashboard cameras. Dashcams are treated the same as any other windshield-mounted device under MCA 61-9-405. A dashcam attached to the windshield constitutes nontransparent material and could be cited if it obstructs the driver's view.

For legal compliance, the recommended placement options are:

• Behind the rearview mirror: This position minimizes obstruction since the mirror already blocks that portion of the windshield. However, even this placement technically involves attaching a nontransparent device to the windshield.
• Dashboard-mounted dashcams: Some dashcam models are designed to sit on the dashboard rather than attach to windshield glass.
• Mirror-integrated dashcams: Replacement rearview mirrors with built-in cameras avoid the windshield mounting issue entirely.

Audio Recording Considerations

Montana is a two-party consent state for audio recording. If your dashcam records audio inside the vehicle, all occupants must consent to the recording. Failing to obtain consent may violate MCA 45-8-213, which governs illegal interception of communications.

Video-only recording of public roadways does not trigger the same consent requirements, since there is no reasonable expectation of privacy on public roads.

Windshield Tinting Restrictions

MCA 61-9-405 also governs window tinting and sunscreening on Montana vehicles. The rules for the windshield differ from those for side and rear windows.

Front Windshield Tint

• Non-reflective tint is allowed only above the manufacturer's AS-1 line (typically the top 5 to 6 inches of the windshield).
• No tint of any kind is permitted below the AS-1 line.
• Tint above the AS-1 line may not be red, yellow, or amber in color.

Front Side Windows

• Light transmission may not be less than 24% visible light transmission (VLT), so a reading of exactly 24% is lawful.
• Reflectance must not exceed 35%.

Rear and Back Side Windows

• Light transmission may not be less than 14% visible light transmission, so a reading of exactly 14% is lawful.
• Reflectance must not exceed 35%.
• MCA 61-9-405(4)(c) carves out the rear window and the side windows behind the front seat on a multipurpose vehicle, van, or bus. Those windows are outside the 14% floor entirely.

Factory Tinting Exemption

MCA 61-9-405(7) switches off the subsection (4) sunscreening restrictions for a multipurpose vehicle (SUV, minivan, crossover) equipped with tinted windows installed by the manufacturer. Subsection (4) is the restriction itself; subsection (7) is where the exemption lives. The same exemption extends to hearses, ambulances, government vehicles, and any vehicle to which a currently valid certificate of waiver under MCA 61-9-428 is affixed.

Medical Waiver for Tinting

Under MCA 61-9-428, the highway patrol or a local law enforcement agency may grant a waiver of the 61-9-405(4) standards for reasons of safety or security or for medical reasons. The affidavit requirement attaches to the medical ground specifically: a medical waiver rests on an affidavit signed by a licensed physician, licensed physician assistant, or advanced practice registered nurse. The waiver must be in writing and must include:

• The vehicle identification number or registration number
• The date of issuance
• The name of the vehicle owner
• The reason for the waiver
• The effective dates
• The signature of the law enforcement officer granting the waiver

Exemptions from Windshield Restrictions

Montana law provides limited exemptions to the windshield obstruction rules:

There is no specific exemption for electronic devices, GPS units, or toll transponders mounted on the windshield. The statute also contains no carve-out for stickers, decals, or certificates displayed on the glass, so nothing in MCA 61-9-405 authorizes an obstruction on the ground that a document is required to be shown.

Penalties for Violations

Violations of MCA 61-9-405 are misdemeanors, but which penalty applies depends on the part of the statute you break.

Windshield obstruction under 61-9-405(2) carries no penalty of its own, so it falls to the chapter-wide schedule in MCA 61-9-511, which sets graduated fines:

MCA 61-9-511 does not authorize jail as a sentence for the offense itself. Jail appears only in 61-9-511(4), and only after a fine goes unpaid, the defendant has no property that can satisfy it, and the court makes a written finding that community service is inappropriate.

Illegal window tint is the exception to that schedule. Under MCA 61-9-429, a violation of 61-9-405(4) is a misdemeanor punishable as provided in MCA 46-18-212: up to 6 months in county jail, a fine of up to $500, or both. Both the vehicle owner or operator and the person who applied the illegal tinting can be charged.

Points and Insurance Impact

A windshield obstruction citation is a non-moving violation in most cases. It typically does not add points to your driving record. However, if the obstruction contributes to an accident, the citation could be used as evidence of negligence in a civil liability claim, which may affect insurance rates.

Montana's Distracted Driving Landscape

Montana stands alone as the only state in the country without a statewide ban on texting while driving or handheld cell phone use behind the wheel. As of 2026, there is no statewide hands-free driving law.

SB 359: The Failed 2025 Attempt

Senate Bill 359, known as "Chloe's Law," was introduced during the 2025 legislative session by Senator Sara Novak (D-Anaconda). The bill would have prohibited handheld use of an electronic device while driving and allowed hands-free communication through earpieces, wrist devices, or voice commands.

SB 359 passed the Montana Senate but was tabled in the House Judiciary Committee. Two attempts to bring the bill to the House floor during the final weeks of the session both failed. The bill died on May 23, 2025, leaving Montana as the only state without a statewide distracted driving law.

Local Cell Phone Ordinances

While there is no statewide law, several Montana cities have enacted their own restrictions:

Drivers passing through these cities should be aware that local ordinances apply even though there is no statewide prohibition. Fines and enforcement vary by municipality.

How This Affects Device Mounting

The lack of a statewide hands-free law creates an unusual situation in Montana. While you are not required by state law to use a hands-free device, you are also restricted from mounting that device on your windshield. The practical result is that dashboard mounts, vent clips, and console mounts become the most legally sound options for using navigation or communication devices while driving.

In cities with local hands-free ordinances, using a dashboard-mounted phone with voice commands or a Bluetooth connection satisfies both the local cell phone law and the state windshield obstruction statute.

Commercial Vehicle Considerations

Commercial motor vehicle (CMV) operators in Montana must comply with both state law and federal regulations. The Federal Motor Carrier Safety Administration (FMCSA) prohibits CMV drivers from using handheld mobile devices while driving under 49 CFR 392.82. This federal rule applies regardless of Montana's lack of a statewide cell phone law.

CMV drivers may use a hands-free device, but it must be positioned so that the driver can operate it without reaching in a way that removes the seat belt from the body. A dashboard mount that keeps the device within arm's reach without requiring the driver to lean or stretch is the recommended setup.

Hands-Free Interaction Best Practices

Even without a statewide requirement, using hands-free technology in Montana is the safest approach for both legal compliance and road safety. Here are recommended practices:

• Use voice-activated navigation: Set your destination before driving and rely on audio directions rather than looking at a screen.
• Mount devices on the dashboard: Keep the windshield clear while still having a visible display for navigation.
• Enable Bluetooth: Pair your phone with your vehicle's audio system for calls and media.
• Pull over for extended interactions: If you need to type an address, read a message, or interact with your phone at length, pull to a safe location off the roadway.
• Use vehicle-integrated systems: Many newer vehicles include built-in navigation and phone integration through Apple CarPlay or Android Auto, eliminating the need for any mounted device.

Toll Transponders and Other Small Devices

Montana does not operate any toll roads, so toll transponders are not a common concern for local drivers. However, drivers traveling to and from states with toll systems (such as the E-ZPass network) may have transponders mounted on their windshields.

Montana law does not include a specific exemption for toll transponders. A small transponder mounted near the top of the windshield is unlikely to "materially obstruct" a driver's view, but it technically falls under the nontransparent material prohibition. Drivers transiting through Montana with a toll transponder should be aware that enforcement is possible, even if unlikely for a small, well-placed device.

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