Ignition interlock in Montana
Montana does not force every driver to install an ignition interlock device by law. What decides it for you is the court order or the letter about your license. If your order or license letter requires an interlock, you can choose from three approved companies. Call us and we'll pass your request to an installer that serves Montana to set up an appointment.
- Statewide requirement
- there isn't one; the paper from your court or the letter about your license decides
- Approved companies
- the three you can pick from are Intoxalock, Smart Start and LifeSafer
- A second DUI within 10 years
- your license is suspended for 1 year
- Agency in charge
- Montana Motor Vehicle Division
- A first DUI conviction brings a 6-month license suspension; check your court order or license letter to see whether you also need an interlock.
5 interlock companies in Montana
| Company | From, a month | Installation | 12 months, install included | Trustpilot |
|---|---|---|---|---|
 LifeSafer | From $50 | $70 to $150 | From $670 | 4.6 of 5 |
 Intoxalock | From $54.99 | Set by each service center | From $729.88install at MADD's typical range | 4.4 of 5 |
 Smart Start | From $59.99 | From $150 | From $869.88 | 4.6 of 5 |
 ALCOLOCK | From $60 | $70 to $150 | From $790 | 2.3 of 5 |
 Dräger (RoadGuard Interlock) | Call for a quoteFirst month free | 1.7 of 5 | ||
Prices are each company's national starting price. The 12-month column adds a year of that price, the install price and any set-up fee, or MADD's typical $70 to $150 where no install price is posted.
MADD's national range: $70 to $150 to install, then $60 to $80 a month, or $790 to $1,110 for a year.
Is an interlock something you need in Montana?
An interlock is a small breath tester that gets wired into your car. Blow a clean sample and the engine starts. Montana does not make every driver install one. A judge can order one, though, so the paperwork in your hands is where to look.
After a DUI conviction, or a conviction for driving with a BAC of 0.08 percent or more, the state can limit you to driving only a vehicle with an interlock. BAC stands for blood alcohol level, meaning how much alcohol was in your blood at the time of the test.
License suspensions that come with a DUI
How long you lose your license for depends on your past record and how old you are, as set by the Motor Vehicle Division.
With a second or later DUI charge or conviction, the court can also order breath tests twice a day, or have you wear a bracelet that tracks alcohol. That order is separate from an interlock order, so go through your court papers carefully to see what applies in your case.
Where to get your interlock in Montana
The Motor Vehicle Division approves Intoxalock, Smart Start and LifeSafer, with LifeSafer listed through #1 A LifeSafer of Montana. Choosing one of them keeps you on the state's approved list.
All three companies publish national starting prices. Monthly leases start at $54.99 at Intoxalock and $59.99 at Smart Start, and LifeSafer charges $50 to $120 a month plus $70 to $150 to install. Those are national numbers, so what you're quoted in Montana may differ.
Total interlock cost over your order
Nationwide, MADD estimates installation at $70 to $150, then $60 to $80 per month while you keep the device. Over 6 months, that adds up to roughly $430 to $630. Over 12 months, figure about $790 to $1,110.
What you pay depends most on how long the order runs. That length is written in your court order or license letter, so keep it handy when you request a price.
What does Montana require of every approved device?
The state department writes the rules covering which devices get approved, plus how they're installed, calibrated, repaired and taken out, and those rules have to follow federal standards for devices of this kind. Calibration is the check-and-adjust work that keeps the readings accurate.
A device approved in Montana has to:
- take a deep lung breath sample, or measure blood alcohol some other way that's just as accurate
- stay accurate and reliable on its own, even in extreme weather
- resist tampering and keep proof if someone tries it
Tampering with the device
Tampering means messing with the device or working around it so the car starts without a proper test. Montana law requires every interlock lease to warn that knowingly tampering with, bypassing or misusing the device can lead to criminal prosecution. Approved devices must show evidence of attempted tampering.