Montana DUI Laws

Montana DUI / DWI Laws

Montana DUI / DWI Laws: Penalties, Fines, Requirements & Information

Montana DUI / DWI Laws Overview & Common DUI / DWI Questions


Q. I’ve been arrested for DUI in Montana, what should I do?

A. If you’ve been arrested for DUI / DWI in Montana, the first thing you should do is talk with an experienced Montana DUI lawyer!  Montana DUI laws are complex and an experienced Montana DUI lawyer will be able to negotiate the best possible outcome.  Call 1.855.700.0754 for a FREE Montana DUI consultation with a local DUI lawyer.

Q. What is the legal blood alcohol content (BAC) limit in Montana?

A. Like all other states in America, the BAC legal limit in Montana for individuals over 21 is .08%.  Montana does have a zero-tolerance law meaning anyone under the age of 21 will be charged with DUI for a BAC greater than .02%.  The commercial BAC limit in Montana is .04%.  Anyone found to have a BAC higher than these limits will be charged with DUI in the state of Montana.

Q. Does Montana have an aggravated DUI charge if my BAC is extremely high?

A. Unlike most other states in America, Montana does not have a enhanced or aggravated DUI charge if convicted of a DUI.

Q. Do I have to take a field sobriety test or chemical test in Montana?

A. Montana DUI laws include “implied consent”, which means you are required to submit to field sobriety tests or chemical testing, or you will face serious consequences.  On the 1st refusal you will face a 6 month license suspension.  Both 2nd and 3rd refusals will result in a year license suspension and possible fine.

Q. If I’m convicted of DUI in Montana will I lose my car?

A. Yes, it is a possibility that your vehicle could be confiscated if you are charged with a DUI offense in Montana.

Q. Can I lose my drivers license if convicted of DUI / DUII in Montana?

A. Yes, license suspension or revocation will occur if you are convicted of DUI / DUII in Montana.  The duration of a suspension varies by the type of DUI offense in Montana.

Q. Will I have to use an ignition interlock device if I’m convicted of DUI in Montana?

A. Yes, Montana DUI laws require the use of ignition interlock devices upon a DUI conviction.

Q. How much does a DUI in Montana cost?

A. A first time DUI conviction in Montana can cost between $7,000 – $10,000.

Q. Will an Montana DUI conviction increase my auto insurance?

A. Yes, definitely.  If you are convicted of DUI / DUII in Maine, your insurance could increase by $3,600 to $6,000.


Overview of Montana DUI / DUII Laws: Penalties, Fines, Jail Time & Requirements

Penalties & Fines For First DUI Conviction in Montana

  • Imprisonment – 2 days to 6 months
  • Fine – $300 to $1,000
  • Mandatory – Alcohol assessment &  treatment with the possibility of ignition interlock device
  • Drivers license suspension – 6 months

Penalties & Fines For Second DUI Conviction in Montana

  • Imprisonment – 7 days to 6 months
  • Fine – $600 to $1,000
  • Mandatory – Alcohol assessment &  treatment with ignition interlock device
  • Drivers license suspension – 1 year

Penalties & Fines For Third DUI Conviction and Subsequent DUI’s Within 10 Years in Montana

  • Imprisonment – 30 days to 1 year
  • Mandatory – Alcohol assessment &  treatment with ignition interlock device
  • Fine – $1,000 to $5,000
  • Drivers license suspension – 1 year

Montana DUI Laws Apply To All Counties in Montana


  • Beaverhead County
  • Big Horn County
  • Blaine County
  • Broadwater County
  • Carbon County
  • Carter County
  • Cascade County
  • Chouteau County
  • Custer County
  • Daniels County
  • Dawson County
  • Deer Lodge County
  • Fallon County
  • Fergus County


  • Flathead County
  • Gallatin County
  • Garfield County
  • Glacier County
  • Golden Valley County
  • Granite County
  • Hill County
  • Jefferson County
  • Judith Basin County
  • Lake County
  • Lewis And Clark County
  • Liberty County
  • Lincoln County
  • Madison County


  • McCone County
  • Meagher County
  • Mineral County
  • Missoula County
  • Musselshell County
  • Park County
  • Petroleum County
  • Phillips County
  • Pondera County
  • Powder River County
  • Powell County
  • Prairie County
  • Ravalli County
  • Richland County
  • Roosevelt County


  • Rosebud County
  • Sanders County
  • Sheridan County
  • Silver Bow County
  • Stillwater County
  • Sweet Grass County
  • Teton County
  • Toole County
  • Treasure County
  • Valley County
  • Wheatland County
  • Wibaux County
  • Yellowstone County
  • Yellowstone National Park County