Colorado DUI Laws: Penalties, BAC Limit & License (2026)

In Colorado the offense is called driving under the influence (DUI), and Colorado Revised Statutes 42-4-1301 makes it unlawful to drive with a blood alcohol concentration (BAC) of 0.08 percent or more. A first DUI carries five days to one year in jail, a $600 to $1,000 fine, and a nine-month license revocation, with a lesser charge of driving while ability impaired (DWAI) available at 0.05 percent, as the Colorado General Assembly law summary explains.

This guide is part of our DUI Laws by State series.

What counts as a DUI in Colorado

Colorado is unusual in having two separate alcohol-driving offenses. Under Colorado Revised Statutes 42-4-1301, DUI means driving when a person is substantially incapable of safe operation because of alcohol or drugs, and DUI per se applies when the BAC is 0.08 percent or more. The lesser charge, driving while ability impaired (DWAI), applies when alcohol affects the driver to the slightest degree; a BAC above 0.05 but below 0.08 percent gives rise to a permissible inference of DWAI, while 0.05 or less is presumed not impaired. Commercial drivers face a 0.04 percent limit, and drivers under 21 fall under the underage drinking-and-driving law at 0.02 percent. The 0.08 figure is the federal benchmark adopted by every state except Utah, which uses 0.05 percent, as the National Highway Traffic Safety Administration describes.

First-offense DUI penalties in Colorado (jail, fines, revocation)

A first DUI is a misdemeanor. Under Colorado Revised Statutes 42-4-1307, a first DUI or DUI per se carries imprisonment of at least five days but not more than one year, a fine of $600 to $1,000, and 48 to 96 hours of public service. The court may suspend the mandatory minimum jail time if the driver completes alcohol treatment, but jail is mandatory and cannot be suspended when the BAC is 0.20 percent or more. Separately, the Colorado Division of Motor Vehicles imposes a nine-month license revocation for a first DUI. A first DWAI is a lesser misdemeanor with two to 180 days in jail and a $200 to $500 fine, and it does not by itself trigger a DMV revocation. Drivers must also carry SR-22 financial-responsibility insurance to reinstate.

Watch out: The DMV revocation and the criminal court case are two separate proceedings. You can resolve the criminal case and still lose your license through the DMV, and you generally must request a DMV hearing within seven days of the notice to contest the revocation.

Ignition interlock requirements in Colorado

Colorado lets many first offenders keep driving by installing an ignition interlock device through early reinstatement. As the Colorado Division of Motor Vehicles explains, a driver serving a first-DUI revocation may apply for an interlock-restricted license after an initial period, then regain unrestricted driving after a set time on the device. The interlock term lengthens with the severity of the case. A BAC of 0.15 percent or more designates the driver a Persistent Drunk Driver, which requires the interlock for at least two years, and a refusal carries the same two-year interlock requirement. Repeat offenders also face multi-year interlock terms. The device requires a breath sample before the engine starts and at random points during the trip, and it logs every reading for the DMV.

License revocation and the administrative (Express Consent) process in Colorado

Colorado runs two systems at once. The administrative revocation is a civil action by the Colorado Division of Motor Vehicles based on the arrest, separate from the criminal case. For a first DUI or DUI per se at 0.08 percent or more, the revocation is nine months. The arresting officer serves an Express Consent affidavit and notice of revocation that also acts as a temporary permit, and the revocation takes effect unless the driver requests a hearing within seven days. Early reinstatement with an interlock is available after the driver serves an initial portion of the revocation, installs the device, files SR-22 insurance, and enrolls in a Level II alcohol education and therapy program. A driver under 21 with a BAC of 0.02 percent or more faces a separate three-month revocation on a first offense.

Repeat offenses and the Colorado look-back period

Colorado treats prior alcohol-driving convictions more harshly than most states because it has no fixed look-back period for felony enhancement. Under Colorado Revised Statutes 42-4-1301, DUI, DUI per se, and DWAI are class 4 felonies when the violation occurs after three or more prior convictions, and neither that provision nor the definition of a prior conviction in 42-4-1301(1)(j) sets any time limit, so a prior DUI, DUI per se, DWAI, or vehicular alcohol offense counts no matter how long ago it occurred. Shorter windows appear only in sentencing: 42-4-1307(5)(b) removes some sentencing alternatives when the new violation occurred less than five years after a prior one. A second offense carries 10 days to one year in jail and mandatory interlock, and a third carries 60 days to one year in jail. The felony threshold sits at the fourth offense: a fourth or subsequent DUI, DUI per se, or DWAI is a class 4 felony, punishable under 42-4-1307(6.5) by two to six years in prison, or probation with a mandatory 90 to 180 days in county jail. Vehicular assault and vehicular homicide while impaired are separate felonies regardless of offense number.

Watch out: Refusing the breath or blood test does not protect your license. A first refusal triggers a one-year revocation, a Persistent Drunk Driver designation, and a two-year interlock requirement, all harsher than failing the test.

Refusing a breath or blood test in Colorado

Colorado's Express Consent law, in Colorado Revised Statutes 42-4-1301.1, provides that by driving in the state you have agreed to take a breath or blood test if an officer has probable cause for a DUI. According to the Colorado Department of Transportation, a first refusal results in a one-year license revocation, longer than the nine-month revocation for failing the test, and longer revocations follow for subsequent refusals. A refusal also designates the driver a Persistent Drunk Driver, which requires a two-year interlock on reinstatement. Because the refusal consequences are harsher than failing, refusing rarely helps. The driver may contest the revocation at a DMV hearing requested within seven days of the notice.

Can you expunge or seal a DUI in Colorado

Colorado does not allow a DUI conviction to be sealed or expunged. The state's record-sealing law in Colorado Revised Statutes 24-72-706(2)(a) excludes convictions for violations of 42-4-1301(1) or (2), which covers DUI, DUI per se, and DWAI, along with class 1 and class 2 misdemeanor traffic offenses and class A and class B traffic infractions, from sealing eligibility. That means a DUI conviction generally stays on the criminal record permanently and continues to appear on background checks. A DUI charge that ends in a dismissal or acquittal may be sealed, since there is no conviction in that situation. Because Colorado has no look-back period, the conviction also counts as a prior for sentence enhancement indefinitely. People seeking relief sometimes pursue a gubernatorial pardon, which is rare and does not erase the record.

What to do after a DUI arrest in Colorado

A Colorado DUI creates two separate matters: a criminal case in court and an administrative revocation at the DMV. The deadlines are short, so a common first step is to request a DMV hearing within seven days of the Express Consent notice, because missing that window generally means the revocation takes effect automatically. The criminal case proceeds on its own schedule from arraignment through resolution. General information cannot tell you how your case will come out, since the outcome depends on the specific facts, the evidence, and your record. Many people consult a licensed Colorado DUI attorney to understand the charge, the seven-day deadline, and the options for both the criminal case and the DMV case. Keep the arrest paperwork, the Express Consent notice, and any test results in a safe place.

More Colorado Laws

• Colorado Expungement Laws
• Colorado Warrant Search

Frequently Asked Questions

What is the BAC limit in Colorado?

The per se DUI limit is 0.08 percent BAC under 42-4-1301. A BAC above 0.05 but below 0.08 percent can support the lesser DWAI charge. Commercial drivers are limited to 0.04 percent and drivers under 21 to 0.02 percent.

How long do you lose your license for a first DUI in Colorado?

The DMV imposes a nine-month revocation for a first DUI at 0.08 percent or more. A driver may apply for early reinstatement with an ignition interlock device after serving an initial portion of the revocation.

What is the difference between DUI and DWAI in Colorado?

DUI applies at 0.08 percent BAC or substantial impairment, while DWAI is a lesser charge that applies when alcohol affects driving to the slightest degree, generally inferred at a BAC above 0.05 but below 0.08 percent.

Is a first DUI a felony in Colorado?

No. A first DUI is a misdemeanor. DUI becomes a class 4 felony on the fourth offense under 42-4-1301(1)(a), with the felony sentence set by 42-4-1307(6.5), or sooner if it causes serious injury or death and is charged as vehicular assault or vehicular homicide.

Do you need an interlock for a first DUI in Colorado?

Often yes. Early reinstatement requires an interlock, and a BAC of 0.15 percent or more or a test refusal triggers a Persistent Drunk Driver designation with a mandatory two-year interlock.

What happens if you refuse a breathalyzer in Colorado?

Under the Express Consent law, a first refusal triggers a one-year revocation, a Persistent Drunk Driver designation, and a two-year interlock requirement, all harsher than the consequences for failing the test.

Can you get a DUI expunged in Colorado?

No. Colorado's record-sealing law excludes DUI and DWAI convictions. A DUI conviction stays on your record permanently, although a dismissed or acquitted charge may be sealed.

What is the look-back period for DUI in Colorado?

Colorado has no fixed look-back period for felony DUI. Prior alcohol-driving convictions count regardless of age, so three or more priors make the next offense a class 4 felony.