Ignition interlock devices in Missouri

Missouri offers the interlock as a trade: fit the device and you drive immediately on a 90-day restricted privilege, or skip it and sit out a 30-day hard suspension first. The catch is the exit — your installer must certify you finished violation-free before the device comes off, and without that certificate you serve another 30 days. As for how long: 90 days on an immediate restricted privilege with the device (request within 15 days of the notice), against a 30-day suspension plus 60-day restricted privilege without it.

Missouri does not publish a price, so the honest answer is the national one: NHTSA puts installation at $70 to $90 and monitoring at about $70 a month, roughly $3 to $4 a day. A quote far above that is the provider's, not the state's.

A recorded event is not automatically a violation, and that distinction decides most cases. Programs differ in what they count and how they count it: some add time per event, others ignore single events and act on a pattern, and several give you a written escape where a retest within five or ten minutes comes back clean. What is uniform is that the decision is made by Missouri Department of Revenue, Driver License Bureau from the vendor's report, not at the roadside. The mechanics, state by state and with the statute on each, are on our page about violations and lockouts.

Not at the workshop, and not on the date in your paperwork. The state releases you first and the device comes out last: you finish the term including anything added to it, sit a final data download at the service center, let Missouri Department of Revenue, Driver License Bureau review the record, take what it issues to a licensing office to lift the restriction, and only then book the removal. Most programs also require a clean window before any of that starts — 180 days in Washington, the last 30 in New Jersey, three months in Maryland.

Missouri does not fix the number in the statute itself — it is set by the certifying agency in the device standard, and in practice sits between 0.02% and 0.025% BAC. Either way it is far below the 0.08% driving limit, which is why one drink shortly before a test is enough to fail it: the device is testing whether you drank, not whether you are impaired.

Sometimes, and it is usually stricter rather than easier. The common substitute is continuous alcohol monitoring — a transdermal ankle bracelet that watches the person instead of the car, all day rather than at the ignition. North Carolina writes the trade directly into sentencing: 120 days of monitored abstinence can cut a 30-day minimum to ten, and 90 days can replace a seven-day term. The other alternative is not driving at all, which some states allow you to serve out instead, and which costs you the license for the whole period rather than the device.

We index 310 certified installation points across 144 Missouri cities, run by 6 approved providers, with the densest coverage in Springfield, Saint Louis, Kansas City. Install with a provider the state approves rather than the nearest pin on the map: time on an unapproved device does not count toward the term.