What an interlock suspension means

An interlock suspension is not a suspension for breaking a rule — it is a suspension that happens because you did not install or maintain an ignition interlock device when the court or DMV ordered you to. The device itself is a breathalyzer wired into your car's ignition. If you were convicted of a DUI or DWI, or refused a breath test, your state may require you to install one before you can drive again. If you do not install it, or if you install it and then remove it or tamper with it, your license gets suspended.

The suspension stays in place until you have the device installed and the monitoring company reports to your state that it is working. This is different from a DUI suspension, which runs for a set number of months. An interlock suspension is a barrier — you cannot move past it without the device.

Key Takeaways

  • An interlock suspension happens when you fail to install a court-ordered ignition interlock device or when you tamper with one that is already installed.
  • The suspension does not lift until the monitoring company sends proof to your state that the device is installed and functioning in your vehicle.
  • You must pay for the device installation and monthly monitoring fees yourself — these are not covered by the court or state.
  • Once the device is installed and reporting, you can request that your license be reinstated, though the process and timing vary by state.

Why the court orders an interlock device

A judge orders an ignition interlock device as a condition of driving after a DUI or DWI conviction, or sometimes after a refusal to take a breath test. The device prevents you from starting your car if it detects alcohol on your breath. The goal is to keep you from driving impaired while you are still rebuilding your driving record.

Some states make the device mandatory for all DUI convictions. Others require it only for repeat offenders, high blood alcohol content (BAC) readings, or cases where someone was injured. A few states offer it as an alternative to a longer license suspension — you can choose to install the device and keep driving, or refuse it and lose your license for months.

How the suspension happens

The suspension is automatic if you do not install the device by the important date the court gives you. That important date is usually 30 to 60 days after your conviction, but it varies by state and by judge. If you miss it, your state's DMV suspends your license without a hearing or second notice.

The suspension can also happen if you install the device and then remove it, tamper with it, or fail to pay the monthly monitoring fee. The monitoring company reports these violations to your state, and the DMV suspends your license again. Some states also suspend you if the device records a failed breath test — meaning you tried to start your car with alcohol in your system.

Installing the device and getting reinstated

To lift the suspension, you must first find an interlock service provider in your state. Your court order will name the approved providers, or your state's DMV website will list them. You call the provider, schedule an installation appointment, and pay the installation fee — typically $100 to $200. Then you pay a monthly monitoring fee, usually $60 to $100, for as long as the device stays in your car.

Once the device is installed, the monitoring company sends a report to your state's DMV confirming that it is working. This report is what actually lifts the suspension. You do not need to go to the DMV or file paperwork yourself — the provider handles the notification. However, you should check your DMV account or call the DMV a few days after installation to confirm the suspension has been removed.

The length of time you must keep the device in your car depends on your state and your sentence. Some states require it for six months, others for one year or longer. During that time, you must pass all breath tests when you start the car, keep up with monthly monitoring appointments, and pay all fees on time.

What happens if you fail a breath test

If the device detects alcohol when you try to start your car, it locks you out and records a violation. The monitoring company reports this to your state and to the court. A single failed test does not automatically suspend your license again, but repeated failures can trigger a new suspension or extend the time you must keep the device installed.

Some states also require you to notify your probation officer or return to court if you fail a test. Check your court order and ask your monitoring company what the reporting rules are in your state. If you are struggling with alcohol, tell your probation officer or the court — many jurisdictions offer treatment programs as an alternative to longer suspensions.

Costs you will pay

The interlock device is not free. Installation usually costs $100 to $200. Monthly monitoring fees range from $60 to $100 per month, depending on your state and provider. Some states allow you to request a fee reduction if you are low-income, but you must ask — the court does not offer it automatically.

You also pay for your own vehicle maintenance. If the device malfunctions or needs recalibration, the provider charges a service fee. If you move to a different state before the device period ends, you may have to pay to transfer it to a new provider or pay an early removal fee.

Driving with the device installed

Once the device is installed and your suspension is lifted, you can drive normally — with one requirement. Every time you start your car, you must blow into the device. It takes about five seconds. If you pass, the car starts. If you fail, the car will not start and the violation is recorded.

The device also requires rolling retests while you are driving. At random intervals, it will alert you to provide another breath sample. You have a few minutes to pull over safely and blow into the device. If you do not, or if you fail, it records a violation and may honk the horn or flash the lights to alert other drivers that something is wrong.

You cannot remove the device yourself or ask a mechanic to remove it early. Only the monitoring company can remove it, and only after your court-ordered period is complete and the court or DMV gives permission.

Frequently Asked Questions

Can I drive before the device is installed?

No. Once the court orders the device, your license is suspended until the device is installed and the monitoring company reports it to your state. Driving with a suspended license is a separate criminal offense and can result in arrest, additional fines, and a longer suspension.

What if I cannot afford the installation or monthly fees?

Some states and counties offer fee reductions or waivers for people with low income. Contact your state's DMV or the court that ordered the device and ask about hardship programs. You can also ask the monitoring company whether they offer payment plans. However, you must still install the device — inability to pay does not lift the suspension.

Does the interlock suspension count toward my DUI suspension time?

No. The interlock suspension is separate from any other suspension the court ordered. If the court suspended your license for six months and also ordered an interlock device, you serve both penalties. The interlock period usually begins after the initial suspension ends, or they may run at the same time depending on your state.

What if I move to another state before the device period ends?

You must notify the monitoring company and your original state's court or DMV. Some states allow you to transfer the device to a provider in your new state and continue the program there. Others require you to return to the original state to have the device removed. Do not remove it yourself — that is a violation and can result in new criminal charges.

Can I get the device removed early?

Only the court or DMV that ordered it can authorize early removal. You can petition the court for early removal if you have a clean record during the device period — no failed tests, no violations, no missed monitoring appointments — but the judge is not required to grant it. Some states do not allow early removal at all.