Montana Drunk Driving Laws & Penalties: How Much Alcohol Can You Drink and Drive?

Drink and drive laws in Montana

The blood alcohol content (BAC) limit in Montana is 0.08% or 80 milliliters of alcohol per 100 milliliters of blood. Drivers may still face charges for impaired driving even if their blood alcohol content is lower.

One to two standard alcoholic drinks are usually sufficient to obtain or exceed the BAC limit of 0.08%. However, this value should only be used as a general guide because a person’s BAC can vary depending on weight and gender.

It is essential to remember that the goal of this post is to increase awareness of Montana’s drunk driving regulations. This website does not endorse or promote drunk driving in any state or region.

Driving while impaired (DWI) or under the influence (DUI) is forbidden in Montana. Yet, Montana has one of the highest fatality rates in the United States in terms of the number of people killed by drunk drivers per vehicle mile traveled.

Statistics show that 213 vehicle accidents in Montana in 2020 were brought on by drunk driving. The at-fault drivers had blood alcohol levels exceeding 0.08% in 45% of these incidents. 

To stop drunk driving in the state, the government of Montana strictly enforces DUI legislation. So, before driving, you should check your blood alcohol level. Use an alcohol breathalyzer to check whether your blood alcohol level is below Montana’s legal limit.

It is recommended to use a designated driver service, like Uber, a taxi, or a cab, rather than operating a vehicle yourself.

For the most up-to-date information about DWI driving laws and regulations, we suggest visiting the official state website of Montana.

Legal Alcohol Limit When Driving in Montana

Driving requires focusing, reasoning through decisions, and responding fast in an emergency. Alcohol impairs these abilities, placing you and others in danger.

In Montana, you would face charges of driving under the influence if your BAC was proven to be 0.08% or above.

The government set BAC limits to reduce the incidence of tragic events involving drunk drivers.

Although the state’s legal BAC limit is 0.08%, you must be aware that everyone’s body responds to alcohol uniquely.

Some of the following elements may influence your BAC level:

  • gender
  • Weight
  • stress levels
  • alcohol consumption level
  • taking medications

Some individuals may pass out after consuming a few bottles of beer. To ensure you obey the DUI laws in Montana, you must check your blood alcohol content before driving.

You can calculate your maximum alcohol intake before driving using a BAC calculator and chart. However, these methods might not be the best option for everyone, given that everyone’s response to alcohol is unique.

A certified alcohol breathalyzer is still the best method for calculating your BAC.

Punishments for Drinking and Driving in Montana

The degree of a person’s alcohol impairment is influenced by one’s level of intoxication and other factors. An individual typically seems normal when their blood alcohol level is between 0.010% and 0.029%.

However, alcohol-related impairment’s effects become increasingly evident as BAC levels rise.

The laws governing DUI vary from state to state. Administrative and legal repercussions may follow driving under the influence. Assess your blood alcohol level before you drive to avoid penalties.

The DUI penalties in Montana are outlined below to help you get familiarized with the law.

First DUI Offense in Montana

A first-time DUI offender in Montana may face the following punishment:

  • Jail Time: Minimum of 24 hours and a maximum of 6 months imprisonment
  • Fines: $600 to $1,000
  • License Suspension: Six months suspension of driving privileges

Second DUI Offense in Montana

A second DUI offense in Montana may result in the following penalties:

  • Jail Time:  At least seven days up to one-year imprisonment
  • Fines:  $1,200 to $2,000 fine
  • License Suspension: One-year license revocation

Third DUI Offense in Montana

A third DUI offense in Montana may result in the following punishment:

  • Jail Time:  At least 30 days up to one year in jail
  • Fines: $2,500 to $5,000 fine
  • License Suspension: One-year license revocation

Ignition Interlock Device

A second-time DUI offender may be limited to solely using an ignition interlock-equipped car throughout probation if the court approves a probationary license.

However, for a year following the end of the license suspension period, anyone charged with a second or subsequent DUI is only permitted to operate a car with an ignition interlock device. 

The vehicle will be impounded and forfeited if the offender doesn’t install an ignition interlock device.

Implied Consent Law

According to Montana’s implied consent law, anyone with a Montana driver’s license or driving a vehicle within the state is regarded to have consented to a blood, breath, or urine test. 

The peace enforcer must have reasonable grounds to suspect that the driver was operating a vehicle while impaired with alcohol or drugs. Refusal to take the test will result in consequences.

Punishment for Test Refusal

The consequences of a test refusal are generally determined by how many prior offenses the driver has committed within the previous five years.

  •  A $300 administrative fee and a six-month license suspension are usually imposed for the first refusal.
  •  A $300 administrative fee and a one-year license suspension are the penalties for a second refusal within five years of a prior refusal.

Additional Consequences for Driving with a BAC of.08 or Higher

  • A first offense carries a maximum sentence of six months imprisonment and an additional fine of $300 to $1,000.
  • A second offense results in a maximum sentence of one year in imprisonment and an additional fine of $600 to $1,000.
  • A third conviction carries an additional year in prison and an additional fine ranging from $1,000 to $5,000.

There would be an additional prison term and fine if a passenger under the age of 16 were in the vehicle at the time of the offense.

When Can You Drink and Drive in Montana?

The way people respond to alcohol depends on a variety of factors. One aspect that affects a person’s blood alcohol level is their gender. According to studies, men and women have different BACs.

Alcohol dehydrogenase (ADH) levels are significantly higher in men than women. These enzymes are responsible for alcohol metabolism. As a result, men process alcohol more quickly than women.

The information below might be helpful if you’re unaware of how much alcohol you can legally consume before driving in Montana.

However, while the information is based on studies, it might not apply to everyone because everyone’s body responds to alcohol differently.

How Many Bottles of Beers Can You Drink and Drive in Montana?

Drink beer and drive in Montana

According to BAC charts, a lighter person might have a higher BAC.

For instance, after consuming a 12-ounce (350 ml) beer, a man who weighs 180 pounds (82 kilos) might have a blood alcohol content of 0.02%.

However, a woman of the same size who drinks the same quantity of beer might have a BAC of 0.03%.

Restrict your beer consumption to one to two bottles to keep your BAC inside Montana’s legal limit.

How Many Glasses of Wine Can You Consume and Drive in Montana?

A standard wine glass contains 5 oz or 142 ml with up to 12% alcohol.

Similar to the previous example, a 180 pound-man can have a BAC level of 0.02% after having one glass of wine. In contrast, a woman who weighs the same and has the same amount of wine can have up to 0.03% BAC level.  

Hence, one to two glasses of wine are sufficient to meet Montana’s legal BAC limit.

How Much Whiskey or Vodka Can You Drink and Drive in Montana?

Distilled spirits like vodka and whiskey have a 40% alcohol content.

Based on the previous example and the same method of calculating blood alcohol content, it can be surmised that one to two shots of whiskey or vodka is enough to keep your BAC level within the allowable limit.

Sticking to DUI Laws in Montana

There are several misconceptions regarding the impact of alcohol consumption on safe driving. All motorists should be aware of the risks associated with DUI and take all reasonable measures to prevent it.

It is not recommended to drive while impaired by alcohol or any other substance. You lose control of yourself and your vehicle when alcohol enters your system.

You shouldn’t presume that your BAC level and driving abilities are safe even if you’ve just consumed a small amount of alcohol. If you’re intoxicated, you should consider using another form of transportation rather than driving.

Check your blood alcohol content to ensure it is below the legal limit if you intend to drive after drinking. Your blood alcohol level can be precisely determined using a reputable alcohol breathalyzer.

Visit the official webpage of Montana to learn more about state DUI laws.

About the author

Ashley Cresswell

Ashley Cresswell is a former phlebotomist with a passion for road safety. During her time as a phlebotomist, Ashley administered over 1000 blood alcohol tests to impaired drivers and was shocked to discover that many of them were simply uninformed about the legal limits for driving under the influence. As a result, Ashley conducted extensive research on scientific studies and local laws to bring drivers a comprehensive resource on drink and drive limits from around the world.