Ignition interlock providers, compared
The device matters less than the network behind it: how far you drive for a calibration, and what the whole term costs. Coverage below is counted from our own centers database — unique physical locations, not marketing claims.
| Provider | Certified centers | |
|---|---|---|
| Intoxalock | 5,927 | Details |
| Smart Start | 2,604 | Details |
| LifeSafer | 2,203 | Details |
| Low Cost Interlock | 1,250 | Details |
| RoadGuard Interlock | 799 | Details |
| ADS Interlock | 502 | Details |
| Guardian Interlock | 207 | Details |
| Alcolock USA | 195 | — |
Every network, side by side
Centers are unique physical locations in our own database. Approvals are the state lists that name the brand or its device. Price is shown only where the company publishes one. Public actions are court and regulator filings we hold on file, not complaints.
| Provider | Centers | States with centers | State approvals on file | Publishes a price | Public actions |
|---|---|---|---|---|---|
| Intoxalock | 5,927 | 48 | 2 | $54.99 | 4 |
| Smart Start | 2,604 | 49 | 2 | No | 2 |
| LifeSafer | 2,203 | 49 | 2 | $70–$150 | 2 |
| Low Cost Interlock | 1,250 | 31 | 2 | No | — |
| RoadGuard Interlock | 799 | 35 | 2 | No | — |
| ADS Interlock | 502 | 28 | — | No | — |
| Guardian Interlock | 207 | 10 | 1 | No | 2 |
| QuickStart Interlock | — | — | 1 | No | — |
| Monitech | — | — | 2 | No | — |
| Blow & Go | — | — | — | No | — |
| Simple Interlock | — | — | 4 | No | — |
A blank in the price column is the finding, not a gap in our research: Smart Start, Guardian, RoadGuard, Low Cost Interlock publish no rate at all, so the quote you are given is the only number that exists. A blank in the actions column means nothing is on file here, which is not the same as nothing having happened.
National networks
Intoxalock
The largest interlock network in the US by service-center count: 5,928 of the 10,618 installation points we index, across 48 states.
5,927 centers · 48 states
Smart Start
Nationwide provider with its own device line and a large installer network.
2,604 centers · 49 states
LifeSafer
One of the oldest interlock brands in the country, run by the same group as Intoxalock and Alcohol Detection Systems.
2,203 centers · 49 states
Low Cost Interlock
Price-led provider that competes primarily on installation and monthly fees.
1,250 centers · 31 states
RoadGuard Interlock
Operates through Nationwide Interlock, which handles its installations and sales; a national network under the RoadGuard brand.
799 centers · 35 states
ADS Interlock
Installer network under the Alcohol Detection Systems brand, part of the same group as Intoxalock.
502 centers · 28 states
Guardian Interlock
Regional provider with a concentrated service footprint.
207 centers · 10 states
Regional and smaller brands
These operate in a limited set of states, or install through partner shops we have not been able to verify independently yet.