GHSA maintains data on state laws surrounding a number of highway safety issues. Below is information regarding laws in the state of Montana. For more information, consult the State Highway Safety Office.

  • Alcohol Impaired Driving


    Increased Penalty for High BAC Administrative License Suspension on First Offense Limited Driving Privileges During Suspension
    .16 6 months Yes

    Ignition Interlocks

    Mandatory for repeat convictions


    Open Container Laws Repeat Offender Laws
    Yes No


  • Child Passenger Safety

    Child Restraint Required

    Under 6 yrs and under 60 lbs

    Adult Safety Belt Permissible

    6 yrs and older and over 60 lbs

  • Distracted Driving

    No bans on hand-held use, cell phone use, or text messaging for any drivers.

  • Drug Impaired Driving

    DUID Zero Tolerance or Per se Laws for Some Drugs

    • Per se >0 for some drugs

    Marijuana-Specific Laws

    • Possession and Use: Decriminalized and legal for recreational and medical use (effective 10/1/21)
    • Impaired Driving: THC per se (5 ng)
  • Mature Drivers

    Length of Regular Renewal Cycle

    8 years (or 4 years by mail)

    Provisions for Mature Drivers

    75 and over: renewal every 4 years


  • Motorcyclists

    Helmets required for riders under 18. Universal helmet law repealed 1977.

  • Seat Belts

    Type of Law


    Who Is Covered?

    6 and over

    In What Seat?


  • Speed and Red Light Cameras

    Speed Cameras

    No state law or programs

    Red Light Cameras


  • Speeding and Aggressive Driving

    Rural Interstates

    Cars (MPH) Trucks (MPH)
    80 70

    Urban Interstates

    Cars (MPH) Trucks (MPH)
    65 65

    Other Limited Access Roads

    Cars (MPH) Trucks (MPH)

    Day: 70

    Night: 65

    Day: 70 (Light Trucks), 60 (Heavy Trucks)

    Night: 65 (Light Trucks), 55 (Heavy Trucks)

  • Teen and Novice Drivers

    Full Privilege Minimum Age

    16 years

    Learner Stage

    Minimum Age (Years/Months)

    Minimum Duration (Months)

    Required Supervised Driving Hours (Night Hours)

    14 / 6 6 50 (10)

    Intermediate Stage

    Minimum Age (Years/Months)

    Nighttime Driving Restriction

    Passenger Restriction (except family, unless noted)

    15 11 p.m. - 5 a.m.

    First 6 months: no more than 1 under 18

    Second 6 months: no more than 3 under 18