Montana has a range of drug and alcohol laws. You cannot legally possess, sell, or make dangerous drugs in this state, and in fact, you can even face criminal penalties just for having items to use, grow, store, or sell dangerous drugs in Montana. Of course, the state also has laws against drinking and driving.

Here is an overview of the most prominent drug and alcohol laws in Big Sky Country.

DUI Laws in Montana

Montana bans drivers from operating their vehicles while under the influence of drugs or alcohol. If your blood alcohol content (BAC) is over 0.08%, you can be charged with excessive BAC. For commercial drivers, the limit is just 0.04%. 

For a driving under the influence (DUI) charge, you don’t necessarily need a BAC over 0.08%. Instead, you can face charges if your ability to drive has been affected by drugs or alcohol. That includes marijuana, illegal drugs, and prescription drugs.

The legal limit for driving a vehicle with marijuana in your system is 5 ng/ml. But again, you can be charged with a DUI if you are impaired, even if the marijuana level in your blood is lower than the legal limit.

In addition, you can face an aggravated DUI if any of the following apply:

  • You have a suspended or revoked driver license.
  • BAC is 0.16% or higher.
  • You have a court-ordered ignition interlock device on your vehicle. That is a breathalyzer that does not allow you to start your car if your BAC is over a certain limit.  
  • You have a pending DUI or BAC charge.
  • You have refused to take a BAC test.

Zero Tolerance Laws for Montana

Like many other states, Montana has zero tolerance rules for drivers under the age of 21. If you are not legally allowed to drink, you cannot even have a trace of alcohol in your system while operating a vehicle. In other words, you can face charges if your BAC is 0.02% or higher.

Is Marijuana Legal in Montana?

Recreational marijuana is illegal in Montana, but as of 2020, the state is considering legalizing this drug for adults aged 21 and older. In 2016, there were 1,490 arrests related to marijauana. The majority were for possession, while only 77 arrests were for crimes such as selling or trafficking. 

Medical marijuana (MMJ) has been legal in Montana since 2004. Initially, patients had to get this drug from just one licensed provider, but the state overhauled its laws in 2019. At the time of writing, patients can buy MMJ from any licensed provider. All medical products must be tested in a licensed laboratory.

Drug and Alcohol Related Crimes

In addition to banning drinking while driving, Montana also has a lot of other laws related to drugs and alcohol. Here are some of the main drug and alcohol crimes in Montana:

  • Possessing drugs.
  • Possessing drugs with the intent to sell.
  • Selling drugs.
  • Storing drugs.
  • Producing or manufacturing drugs.
  • Possessing precursors to dangerous drugs — for example, the items to make meth.
  • Operating an illegal drug lab.
  • Distributing drugs on school property.
  • Illegally obtaining drugs.
  • Changing labels on drugs.
  • Imitating dangerous drugs.
  • Advertising imitation drugs.
  • Carrying drugs on a train.

Penalties for Drug or Alcohol Abuse in Montana

If caught with dangerous drugs in Montana, you can face serious penalties. As of 2019, here are the penalties for drug possession in Montana.

  • Up to 60 grams of marijuana or 1 gram of hashish — Misdemeanor charge and up to a $500 fine.
  • 2nd offense for up to 60 grams of marijuana — Fine up to $500, up to 6 months in jail, or both.
  • 3rd offense for up to 60 grams of marijuana — Up to $1000 fine, jail for up to 1 year, or both.
  • Possession of all other dangerous drugs or more than 60 grams of marijuana — Up to 5 years in prison, up to a $5000 fine, or both.
  • Possession of drug paraphernalia — If you have drug paraphernalia, you can face up to 6 months in jail, up to a $500 fine, or both. The law defines paraphernalia as anything that you can use to grow, process, test, or store drugs as well as items designed to help you inject, inhale, or put drugs into your body in any other way. 

Note that the penalties for selling or trafficking drugs are much more severe. Additionally, you can face worse charges and stricter penalties for committing these crimes near schools or around minors.

When you are struggling with drug or alcohol addiction, you may make dangerous decisions about possessing drugs or driving vehicles. To protect yourself from being charged with a crime, get help now. To learn more, contact a local treatment center today. 


  1. 45-10-103. Criminal possession of drug paraphernalia, MCA. (n.d.)
  2. 45-9-102. Criminal possession of dangerous drugs, MCA. (n.d.)
  3. Driving under the influence of alcohol/drugs. (n.d.)
  4. Marijuana Policy Project. (n.d.). Montana
  5. Montana medical marijuana program. (n.d.)
  6. Part 1. Offenses involving dangerous drugs – Table of contents, title 45, chapter 9, MCA. (n.d.)

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