Ignition Interlock Device in Colorado

An ignition interlock device, commonly called an IID or simply an interlock, is a breath-testing device installed in a vehicle that prevents the vehicle from being operated when alcohol is detected above the device’s permitted level. Colorado commonly requires ignition interlock following DUI-related driver’s-license revocations, repeat alcohol offenses, high-BAC violations, chemical-test refusals, and certain early reinstatements.

An IID is not the same thing as a police breathalyzer used to determine whether a driver’s BAC was at least 0.08. The device is designed to prevent alcohol-impaired driving by requiring a breath sample before the vehicle starts and additional samples while the vehicle is being operated. Colorado does not simply set the device to allow someone to drive up to the ordinary 0.08 DUI limit; the interlock is designed to respond to much lower alcohol readings established through the state’s interlock program.

Ignition interlock requirements can significantly affect a person’s daily life. Drivers may be responsible for installation, leasing, servicing, removal, insurance, and reinstatement expenses, and violations can extend the amount of time the device is required or cause another license revocation.

If you have been arrested for DUI or DWAI and are concerned about losing your driving privileges or being required to use ignition interlock, an experienced Colorado DUI attorney can help you understand the criminal case and the separate DMV proceedings that determine your driving privileges.

Denver DUI Attorney | Colorado Ignition Interlock Program

An ignition interlock restriction can last for months or years and may affect nearly every vehicle a person is legally permitted to drive. Understanding the DMV requirements is therefore an important part of defending a Colorado DUI case.

If you select Denvers Defense Attorney, attorney Matthew Martin can review the DUI arrest, chemical testing, DMV revocation, prior driving history, and whether the state has correctly imposed an ignition interlock requirement. He can also represent you at a DMV hearing and help determine whether you qualify for early reinstatement or early removal of the device.

Call 303.725.0017 to schedule a free initial consultation. Denvers Defense Attorney represents clients throughout the greater Denver metropolitan area, including Boulder County, Adams County, Broomfield County, Douglas County, Arapahoe County, and Jefferson County.

Overview of Ignition Interlock Devices in Denver, Colorado

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What Is an Ignition Interlock Device?

An ignition interlock device is a breath-testing machine connected to a vehicle’s ignition system. Before starting the vehicle, the driver must provide an acceptable breath sample. If the device detects an elevated alcohol concentration, it prevents the vehicle from starting.

The driver is also periodically required to provide additional breath samples while driving. These are commonly known as rolling retests. Their purpose is to prevent a driver from having another person provide the initial breath sample and then operating the vehicle after consuming alcohol.

A rolling retest does not normally shut off a vehicle’s engine while it is moving. Automatically turning off the engine could create a significant safety hazard. Instead, a failed or missed test is recorded by the device and may trigger warnings or be reported to the interlock provider and Colorado DMV.

The device stores information about the driver’s use of the vehicle. Depending on the approved system, reports may include:

  • Successful breath samples;
  • Alcohol-positive readings;
  • Missed rolling retests;
  • Attempts to start the vehicle after consuming alcohol;
  • Tampering or circumvention events; and
  • Device servicing and calibration information.

The interlock must be installed by a provider approved by the Colorado Department of Revenue. A driver cannot simply purchase a consumer breath-testing device and install it independently.

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When Is an Ignition Interlock Device Required in Colorado?

Colorado can require an ignition interlock-restricted license in several different situations. Some drivers use interlock to regain driving privileges before completing the full period of a DUI-related revocation, while others must use the device for a specified period as a condition of becoming fully licensed again.

Common situations include:

First DUI or DUI Per Se – For qualifying violations occurring on or after January 1, 2023, an adult Colorado resident with a first DUI or BAC-related revocation may be able to reinstate driving privileges as soon as the revocation becomes active by obtaining an interlock-restricted license. A first offense with a BAC below 0.15 generally carries a nine-month interlock period, although certain first-time drivers may qualify for early removal.

High BAC of 0.15 or Greater – A BAC of at least 0.15 results in designation as a persistent drunk driver. A qualifying driver generally faces a two-year ignition interlock requirement after reinstatement.

Multiple DUI or Alcohol Violations – Drivers with multiple alcohol-related violations generally face a two-year interlock requirement. For example, a person with two qualifying alcohol or drug convictions within five years generally must hold an interlock-restricted license for at least two years before becoming eligible for an unrestricted license.

Chemical-Test Refusal – Refusing a lawfully requested breath or blood test results in a persistent drunk driver designation and can require two years of ignition interlock following early reinstatement. Under current law, a qualifying driver generally must serve two months of the refusal revocation before early reinstatement is available.

Habitual Traffic Offender Status – Some habitual traffic offenders whose qualifying history includes an alcohol-related driving offense may be eligible for early reinstatement with ignition interlock. The exact waiting period and interlock duration depend on the person’s driving record and remaining restraint.

Because a driver can have several DMV restraints at the same time, the precise interlock period cannot always be determined solely by looking at the most recent DUI charge.

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How Long Do You Need an Ignition Interlock Device in Colorado?

The required period depends on the driver’s BAC, prior history, test refusal, date of violation, and reason for the license revocation.

For violations occurring on or after January 1, 2023, common interlock periods include:

First DUI or DUI Per Se With BAC Below 0.15 – Generally nine months when the person seeks early reinstatement. The interlock period and nine-month revocation can run concurrently.

First DUI With BAC of 0.15 or Higher – Generally two years because the driver is designated a persistent drunk driver.

Second or Subsequent BAC Violation – Generally at least two years following reinstatement.

Chemical-Test Refusal – Generally at least two years when the driver uses early reinstatement.

Multiple Alcohol or Drug Convictions – A person with two qualifying convictions within five years generally must maintain an interlock-restricted license for at least two years. Drivers with three or more qualifying convictions may have additional revocations and requirements.

The amount of time required can increase if the driver fails alcohol tests, misses required servicing, tampers with the device, drives a vehicle without an IID, or otherwise violates the restricted-license conditions.

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Can a First-Time Driver Have the Interlock Removed Early?

Some first-time offenders with a BAC below 0.15 may qualify for early removal of the ignition interlock device.

Under the current program, a qualifying driver may be able to request removal after completing four consecutive months, or 120 days, without an interlock failure. The driver generally gets one opportunity to request this early removal based on the interlock monitoring record.

If the person does not qualify for early removal, the full interlock period must ordinarily be completed.

Early removal generally is not available on the same terms to persistent drunk drivers, repeat offenders, or drivers whose interlock requirement resulted from a refusal.

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Early License Reinstatement With an Ignition Interlock Device

One of the most important purposes of Colorado’s ignition interlock program is allowing eligible drivers to regain limited driving privileges before serving their entire DUI-related revocation.

For violations occurring on or after January 1, 2023, a qualifying Colorado resident who was at least 21 at the time of the violation may generally seek early reinstatement for a DUI or BAC violation on the first day the revocation becomes active. There is no one-month waiting period for these qualifying cases.

A person seeking reinstatement may be required to:

  • Install an approved ignition interlock device in every vehicle they own or may drive;
  • Submit the required interlock affidavit;
  • Provide copies of the lease and installation certificate;
  • Complete a reinstatement application;
  • Pay DMV reinstatement fees;
  • Obtain SR-22 insurance when required;
  • Enroll in or complete Level II alcohol or drug education and treatment when required; and
  • Obtain an interlock-restricted Colorado driver’s license.

The person may not legally begin driving merely because the device has been installed. The DMV must reinstate the driving privilege and the driver must obtain the appropriate restricted license.

For a chemical-test refusal, current law generally requires the driver to serve at least two months before early reinstatement. Colorado enacted legislation in 2026 that will eliminate that two-month waiting period beginning June 1, 2027, but that change is not yet effective.

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What Happens if You Fail an Ignition Interlock Test?

An alcohol-positive test can prevent the vehicle from starting and will generally be recorded by the device. A single reading does not necessarily cause an immediate one-year extension, but repeated alcohol detections can result in additional DMV penalties.

Colorado DMV states that if the device prevents operation of the vehicle because of alcohol in three of any twelve consecutive months, the driver may face a suspension and an extension of the ignition interlock requirement of up to one year for each qualifying set of failures.

This rule is based on the months in which qualifying alcohol events occur rather than simply counting every individual breath sample.

An interlock reading may occasionally be caused by something other than drinking an alcoholic beverage. Mouthwash, certain foods, medications, or other substances containing alcohol can potentially create readings. If a driver believes a reported violation was inaccurate, retaining records and following the provider’s retesting procedures may become important.

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What Happens if the Interlock Device Malfunctions?

Ignition interlock equipment can experience mechanical, electrical, calibration, or communication issues. A faulty reading or equipment problem can create serious inconvenience because the driver may be unable to start the vehicle or may receive a violation report.

Drivers experiencing a malfunction should generally contact their certified interlock provider promptly rather than trying to repair or disconnect the device themselves. Attempting to alter, bypass, remove, or interfere with the system can be treated as circumvention or tampering.

Keeping documentation may also be important. Records can include:

  • The date and time of the malfunction;
  • Error messages displayed by the unit;
  • Results of immediate retests;
  • Communications with the provider;
  • Repair or servicing records; and
  • Any evidence that could explain an unusual alcohol reading.

If the alleged malfunction results in a DMV extension or suspension, the driver may have procedures available to challenge the action.

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Can You Drive Another Vehicle While Interlock Restricted?

Generally, an interlock-restricted driver must use a properly equipped vehicle. Colorado requires a person seeking interlock reinstatement to install an approved IID in vehicles they own or co-own and other vehicles they may have access to drive.

Driving a vehicle without the required IID is a serious violation. Colorado DMV warns that driving a non-equipped vehicle or attempting to circumvent the device can result in a license revocation with no driving for at least one year.

A driver should therefore not assume that borrowing a friend’s vehicle, driving a spouse’s vehicle, or using a work vehicle is permitted simply because the driver does not own it.

Specific rules and limited exceptions may apply in some employment situations, so the driver should confirm the restriction before operating any vehicle without an IID.

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Servicing and Maintaining an Ignition Interlock Device

Having an IID installed is not enough by itself. The device must remain properly maintained throughout the restricted period.

Colorado currently requires ignition interlock devices to be serviced at least every 60 days. A driver who fails to report for required servicing can have their driving privilege suspended until they return to compliance. If the provider cancels the lease before the restriction is completed, the DMV may also suspend the license until a new qualifying lease is established.

Servicing allows the provider to:

  • Inspect the equipment;
  • Check calibration;
  • Download monitoring information;
  • Review alcohol-positive tests;
  • Identify possible tampering;
  • Repair or replace malfunctioning equipment; and
  • Submit required information to the DMV.

Drivers should keep copies of service records throughout the interlock period.

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How Much Does an Ignition Interlock Device Cost in Colorado?

There is no single statewide price for ignition interlock installation and monitoring. The cost depends on the certified provider, vehicle, installation complexity, required length of use, and additional charges for servicing or removal.

Common costs can include:

  • Initial installation;
  • Monthly lease or monitoring charges;
  • Calibration and servicing;
  • Removal of the device;
  • Lockout or violation-reset fees;
  • Missed appointment charges; and
  • Repairs for damaged equipment.

Because providers establish their own prices within the state-approved program, drivers should obtain quotes directly from authorized Colorado interlock providers rather than relying on a single estimated statewide price.

The total expense can become significant when an interlock is required for two years or longer. These costs may also be added to other DUI expenses such as SR-22 insurance, treatment, DMV reinstatement fees, probation, and court costs.

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Is Financial Assistance Available for an Ignition Interlock Device?

Yes. Contrary to the older version of this page, Colorado does provide financial assistance to some qualifying drivers who are unable to pay the full cost of ignition interlock.

The Colorado Department of Revenue administers a financial-assistance program for qualifying first-time offenders and certain persistent drunk drivers. Assistance can offset part of the lease costs when the applicant meets the program’s eligibility requirements and funding is available. Current DMV information states that assistance can total up to $400 under the existing program.

Eligibility currently includes requirements concerning Colorado residency, age at the time of the violation, financial need, and the nature of the DUI-related restraint.

Colorado also enacted changes to the financial-assistance program in 2026. Beginning June 1, 2027, certified manufacturers will be required to provide specified installation, lease, and removal discounts to qualifying low-income participants under revised eligibility standards.

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Additional Resources

Ignition Interlock Program | Colorado DMV – Visit the Colorado Department of Revenue for current information about who must use ignition interlock, required periods, servicing, violations, extensions, and early reinstatement.

Early Reinstatement With Interlock | Colorado DMV – Review the eligibility requirements for regaining driving privileges before the full revocation period has expired, including the different rules for DUI, excessive BAC, and chemical-test refusal cases.

Colorado’s Laws on Ignition Interlock Devices – Visit the official website for Colorado Revised Statues to read up on their legislation in regard to ignition interlock devices. Access the statutes to find out what DUI crimes require an IID installation, how providers are certified, and more.

Certified Interlock Providers | Colorado DMV– Visit the official website for the Colorado Department of Revenue (CDOR) to access a list of state-approved interlock providers certified under Colorado law. Access their sites to find a price quote, get answers to your frequently asked questions, and obtain contact information from IID providers.

Financial Assistance for Ignition Interlock | Colorado DMV – Learn about the state program that can help qualifying drivers pay a portion of their ignition interlock costs.

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Denver DUI Lawyer for Ignition Interlock Issues

An ignition interlock requirement can last months or years and can substantially affect a person’s transportation, employment, finances, and everyday responsibilities. Violations of the program can also lead to extended restrictions or an additional period in which the person cannot legally drive at all.

If you have been arrested for DUI or DWAI, received an ignition interlock restriction, or are facing allegations that you violated the interlock program, Denvers Defense Attorney can help you understand the criminal and DMV consequences involved. Attorney Matthew Martin can review the DUI evidence, challenge an improper license revocation, represent you at an administrative hearing, and determine whether you qualify for early reinstatement or removal of the device.

Call 303.725.0017 to schedule a free initial consultation. Denvers Defense Attorney represents clients throughout Denver and surrounding counties, including Boulder County, Adams County, Broomfield County, Douglas County, Arapahoe County, and Jefferson County.

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