When Is an Ignition Interlock Device Required in Utah?

 Posted on April 24, 2026 in DUI

An ignition interlock device is a small breathalyzer that is installed in your car and connected to the ignition, not allowing the car to start until the driver successfully passes a test. In Utah, ignition interlock devices are required in many DUI cases, and the rules around when they are mandatory have gotten stricter in recent years. If you are facing a DUI charge in 2026 and want to understand how this device could affect your life and your ability to drive, Collins Rupp, P.C. can help. Our Davis County, UT DUI defense lawyers can explain how the device works and what it means for your driving privileges.

How Does an Ignition Interlock Device Work?

Once the device is installed, you have to blow into it before the engine will start. Most devices also require what are called rolling retests, which are breath samples taken at random times while the car is moving. If you fail a retest or do not provide one when asked, the device logs it and reports it. It will not shut the car off while you are driving. However, the violation goes on your record with the monitoring provider and gets reported to the court.

All ignition interlock devices used in Utah have to be approved by the state and installed by a certified provider. You are responsible for the cost of installation, monthly calibration, and monitoring fees, which can add up over time.

When Is an Ignition Interlock Device Required in Utah?

Utah Code § 41-6a-518 explains when ignition interlock devices are required. The rules depend on how many prior DUI convictions you have and the details of your current offense. In general:

• A first DUI conviction requires an ignition interlock device for 18 months if your blood alcohol content was 0.16 percent or higher for a driver who is at least 21 years old. For drivers under 21, the requirement is for three years.

• A first DUI with a BAC below 0.16 percent may still result in an interlock requirement, depending on what the court orders.

• A second DUI conviction within 10 years requires an ignition interlock device for two years, or three years if it was a felony DUI conviction.

It is also important to know that Utah has one of the lowest legal BAC limits in the country. Under Utah Code § 41-6a-502, the legal limit is 0.05 percent, which is lower than the 0.08 percent limit used by most other states. This means more drivers can be charged with DUI in Utah at lower alcohol levels, and the interlock rules apply to those convictions just the same.

Can You Drive Without an Ignition Interlock Device During the Required Period in Utah?

If an ignition interlock device is required as part of your DUI case, you cannot legally drive any vehicle that does not have one installed during that time. This includes borrowed vehicles, rental cars, and vehicles owned by others in your household if you are expected to drive them. Driving without the required device is a separate offense that can bring new charges and extend the interlock period.

There is a limited exception for driving a vehicle owned by your employer during work hours, but this requires proper paperwork and does not apply if you own the business.

What Happens if You Tamper With or Bypass an Ignition Interlock Device in Utah?

Trying to tamper with, disconnect, or get around an ignition interlock device is a criminal offense in Utah. It can lead to new charges, a longer interlock period, and in some cases, the loss of your driving privileges entirely. The devices are built to detect tampering and record any suspicious activity. That data is reviewed regularly and reported to the court or the Driver License Division as required.

Does the Interlock Requirement Affect Your License Reinstatement in Utah?

In Utah, completing the ignition interlock requirement is directly tied to getting your full driving privileges back. If you remove the device early, fail to keep it properly maintained, or rack up violations during the monitoring period, it can delay or block your license from being fully reinstated. The IID requirement is extended by 60 days for each failure to have the device monitored or each attempt to start the vehicle with a measurable amount of alcohol. The Driver License Division tracks your compliance, and problems during the interlock period can mean more time before you are allowed to drive normally again.

Can a DUI Charge Be Fought To Avoid the Interlock Requirement in Utah?

If the charge is reduced to a lesser offense or dismissed, the mandatory interlock requirement may not apply at all. Even when a conviction is likely, negotiating the terms of a plea can sometimes affect the conditions the court puts in place, including how long the interlock requirement lasts.

Schedule a Free Consultation With Our Salt Lake City DUI Defense Attorneys

An ignition interlock requirement can affect your daily life for years, and that is just one part of what a DUI conviction in Utah can cost you. The Davis County, UT DUI defense lawyers at Collins Rupp, P.C. can help you navigate the entire DUI defense process. Call 385-777-2753 to schedule your free consultation and discuss the options that are available to you.