Montana motorcycle laws require every street rider to hold a motorcycle endorsement, carry liability insurance, keep the headlight on at all times, and meet basic equipment standards, but the state imposes no helmet requirement on adults and is one of the few that permits lane filtering. The rules below cover what you need to ride legally on Montana roads.
Motorcycle Endorsement
You cannot legally ride on Montana roads without a motorcycle endorsement added to your driver’s license.1Montana Legislative Services Division. Montana Code 61-5-102 – Drivers To Be Licensed – Penalty Getting one requires an eye exam, a written knowledge test covering Montana traffic laws and motorcycle-specific content, and a skills test to show you can control the bike.2Montana Code Annotated. Montana Code 61-5-110 – Records Check of Applicants – Examination
Completing a Basic Rider Course through Montana Motorcycle Rider Safety waives the on-bike skills test at the DMV. You still take the written exam.3Montana Motorcycle Rider Safety. Montana Motorcycle Rider Safety FAQs
Riding without the endorsement is a misdemeanor. A first offense carries a fine of up to $500 and up to six months in jail. Second and later convictions add a mandatory minimum of two days in jail on top of the same fine.4Montana State Legislature. Montana Code 61-5-102 – Drivers To Be Licensed – Penalties
Helmets and Eye Protection
Montana requires helmets only for riders and passengers under 18. The headgear must meet standards set by the Montana Department of Justice and applies any time the motorcycle is on a public street or highway. Riders inside a fully enclosed autocycle with a windshield, doors, and a roof are exempt.5Montana State Legislature. Montana Code 61-9-417 – Headgear Required for Minor Motorcycle Riders
Adults face no helmet mandate. Montana’s windshield statute explicitly exempts motorcycles from the requirement to have a windshield, so most riders are exposed to road debris and wind at all times.6Montana Code Annotated. Montana Code 61-9-405 – Windshields Required, Exception Goggles, a face shield, or riding glasses are not written into a separate statute as an adult requirement, but the practical case for them is obvious.
Lane Filtering and Lane Sharing
Since October 2021, a rider on a two-wheeled motorcycle may pass another vehicle in the same lane when that other vehicle is stopped or moving at 10 mph or less. Three conditions apply:
- The lane must be wide enough for the motorcycle to pass safely.
- The filtering motorcycle cannot exceed 20 mph.
- Overall conditions must allow the rider to continue operating safely.
Passing a vehicle moving faster than 10 mph, exceeding 20 mph while overtaking, or squeezing through a gap that is too narrow falls outside the statute and exposes the rider to standard traffic violations.7Montana Code Annotated. Montana Code 61-8-392 – Lane Filtering for Motorcycles
Two motorcycles may also ride side by side in a single lane, but only with the consent of both riders. No vehicle may be driven in a way that deprives another vehicle of full use of a lane, so a third bike in the same lane is not allowed.8Montana Code Annotated. Montana Code 61-8-359 – Riding on Motorcycles or Quadricycles
Required Equipment
Every street motorcycle needs at least one headlamp, at least one tail lamp emitting red light visible from 500 feet to the rear, and a white light illuminating the rear plate so it can be read from 50 feet back.9Montana Code Annotated. Montana Code 61-9-203 – Headlamps on Motor Vehicles10Montana Code Annotated. Montana Code 61-9-204 – Taillamps – Definition You must also have a mirror providing a view of the road for at least 200 feet behind the bike.11Montana Code Annotated. Montana Code 61-9-404 – Mirrors
The exhaust system must include a muffler in good working order. Muffler cutouts and bypass devices are illegal on any highway.12Montana Code Annotated. Montana Code 61-9-403 – Mufflers – Prevention of Noise
Headlights must be on whenever the motorcycle is on public roads, including in daylight. Collector’s-item bikes get a narrow exception between half an hour before sunrise and half an hour after sunset if visibility is good.8Montana Code Annotated. Montana Code 61-8-359 – Riding on Motorcycles or Quadricycles
Carrying a Passenger
A motorcycle may carry a passenger only if the bike is designed for more than one person. The passenger must sit on a permanent two-person seat or on a separate seat firmly attached to the rear or side of the operator’s position, and cannot sit anywhere that blocks the operator’s view or interferes with control. Passengers sit astride, facing forward, one leg on each side. The operator cannot carry packages that force one-handed riding or otherwise interfere with safe handling.8Montana Code Annotated. Montana Code 61-8-359 – Riding on Motorcycles or Quadricycles
Insurance Minimums
Every motorcycle operated on Montana roads must carry liability insurance meeting minimum limits of $25,000 for bodily injury to one person, $50,000 for bodily injury to two or more people in a single crash, and $20,000 for property damage.13Montana Code Annotated. Montana Code 61-6-103 – Motor Vehicle Liability Policy Minimum Limits – Other Requirements Proof of insurance must be available during registration and while riding.
Penalties escalate with each conviction. A first offense carries a fine of $250 to $500. A second within five years brings a $350 fine. A third or later conviction adds up to 10 days in jail.14Montana State Legislature. Montana Code 61-6-304 – Penalties Given motorcycle repair costs and the medical bills that follow even a minor crash, many riders carry well above these minimums.
Registration and License Plate
Montana registers motorcycles permanently, regardless of the bike’s age. The one-time fee for a motorcycle used on public highways is $53.25, plus a $16 motorcycle safety fee and a $10 additional fee. Adding off-highway registration brings the combined fee to $114.50 plus the safety and additional fees. Temporary registrations under a separate provision run $44 per year for highway use plus a $7 annual safety fee.15Montana Code Annotated. Montana Code 61-3-321 – Registration Fees of Vehicles and Vessels
A single license plate goes on the rear of the motorcycle. It must be securely fastened to prevent swinging and remain plainly visible at all times.16Montana State Legislature. Montana Code 61-3-301 – Registration – License Plate Required – Display
Hand Signals
When electronic turn signals are not visible or not working, Montana requires hand-and-arm signals given from the left side of the bike. A left turn is signaled by extending the arm horizontally. A right turn by extending the hand and forearm upward. Slowing or stopping by extending the hand and arm downward.17Montana State Legislature. Montana Code 61-8-378 – Method of Giving Hand-and-Arm Signals One hand off the bars changes the dynamics of control, so knowing these cold matters more than it does in a car.
Reporting a Crash
If a motorcycle crash causes any injury, death, or property damage over $1,000, the operator must file a written accident report with the state within 10 days. The exception is when a law enforcement officer investigates the scene and files the report instead.18Montana Code Annotated. Montana Code 61-7-109 – Written Reports of Accidents The $1,000 threshold is lower than many riders expect. A cracked fairing, bent bars, and scratched tank reach it quickly.
DUI on a Motorcycle
Montana’s DUI laws apply to motorcycles the same as any other motor vehicle. A first offense carries a mandatory minimum of 24 consecutive hours in jail (up to six months) and a fine between $600 and $1,000. If a passenger under 16 is on the bike, both the jail time and the fine double. Courts also require completion of a chemical dependency education course. The mandatory minimum jail time cannot be served under home arrest and cannot be suspended unless a judge finds that imprisonment would endanger the person’s health.19Montana Code Annotated. Montana Code 61-8-1007 – Penalty for Driving Under Influence – First Through Third Offenses
Off-Road Motorcycles
A motorcycle built for off-road use is classified as an off-highway vehicle unless it has been modified to meet street equipment standards and registered for highway use.20Montana State Legislature. Montana Code 61-1-101 – Definitions Riding on public land or trails requires OHV registration and, for Montana residents, an OHV Resident Trail Pass covering motorized routes on U.S. Forest Service and certain BLM lands. OHVs used exclusively on private property are exempt from registration, trail pass, and titling requirements.21Montana Fish, Wildlife & Parks. Off-Highway Vehicles To ride on paved highways, the vehicle must meet full street-legal equipment standards and carry a standard license plate.