Ignition Interlock Companies in Canada and the United States

What is an ignition interlock?

An ignition interlock device (IID), sometimes called a car breathalyzer, is installed in your vehicle after an impaired driving or DUI offence. You give a breath sample before the engine starts and at random times while you drive. If the device detects alcohol, the vehicle will not start and the result is reported to your licensing agency.

Find an interlock provider

In Canada, each province approves one or two companies, so the choice is usually made for you. Our Canada page lists the approved provider in each province with phone numbers.

In the United States, most states certify several companies. Our United States page explains how to compare providers on certification, service centre locations, cost and support.

What to expect

1. Get approved: your licensing agency or court tells you when you need an interlock and for how long.
2. Book an installation: call an approved provider and choose a service centre near you.
3. Keep your appointments: the device is downloaded and calibrated on a regular schedule, often every 30 to 60 days.
4. Finish the program: when your agency confirms you are done, the provider removes the device.

For interlock companies

Reach drivers at the moment they need an interlock. One flat yearly listing puts your company on this site and on our network of eight Canadian impaired driving lawyer directories. Contact us to list your company.

Ignition interlock questions

What is an ignition interlock device?

An ignition interlock device (IID) is a breath-alcohol tester connected to a vehicle's ignition. The driver must pass a breath test before the engine starts and at random times while driving.

Who has to install an ignition interlock?

Usually drivers convicted of impaired driving or DUI, and in many provinces and states drivers who want a restricted or early licence after a suspension. Your licensing agency or court order says whether you need one.

Can I choose my interlock company?

In Canada, most provinces approve only one or two providers, so the choice is usually made for you. In the United States, most states certify several companies and you can compare them.

This site is an independent directory. We are not affiliated with any government agency or interlock manufacturer, and nothing here is legal advice.