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

In Illinois the offense is called driving under the influence (DUI), and 625 ILCS 5/11-501 makes it unlawful to drive with a blood alcohol concentration (BAC) of 0.08 percent or more. A first DUI is a Class A misdemeanor punishable by up to one year in jail and a fine of up to $2,500, and a conviction triggers a license revocation of at least one year.

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

What counts as a DUI in Illinois

Illinois's core impaired-driving statute, 625 ILCS 5/11-501, makes it unlawful to drive or be in actual physical control of a vehicle with a BAC of 0.08 percent or more, or while under the influence of alcohol, drugs, or an intoxicating compound to a degree that renders the person incapable of driving safely. Because the impairment branch does not require a specific number, a driver below 0.08 can still be convicted. Commercial drivers face a 0.04 percent limit, and drivers under 21 fall under the state's zero-tolerance law, which suspends the license of any underage driver who registers any trace of alcohol. 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. A BAC of 0.16 percent or more adds mandatory penalties on top of the base first-offense sentence.

First-offense DUI penalties in Illinois (jail, fines, suspension)

A first DUI is a Class A misdemeanor under 625 ILCS 5/11-501(c), punishable by up to one year in jail and a fine of up to $2,500, with no mandatory minimum jail for a standard first offense. If the driver's BAC was 0.16 percent or more, the statute adds a mandatory minimum $500 fine and 100 hours of community service. A first offender who meets the criteria may receive court supervision, a disposition that, if completed successfully, avoids a conviction on the record, though it is available only for a first DUI with no death or serious injury. A conviction, by contrast, triggers a mandatory driver's license revocation of at least one year under 625 ILCS 5/6-208.1. Court costs and reinstatement fees apply on top of the fine.

Watch out: The statutory summary suspension and the criminal DUI case run on separate tracks. The Secretary of State suspends your license based on the test result even if the criminal charge is later reduced or dismissed, and you generally must file to challenge the summary suspension before it takes effect on the 46th day after notice.

Ignition interlock requirements in Illinois

Illinois ties its interlock rules to the summary suspension through the Monitoring Device Driving Permit (MDDP). A first offender whose license is under a statutory summary suspension may apply for an MDDP, which lets the person drive anywhere, anytime, provided every vehicle the person drives is equipped with a Breath Alcohol Ignition Interlock Device (BAIID). The device requires a breath sample before the engine starts and at random intervals during a trip, and it records every reading for the Secretary of State. The MDDP is available to first offenders who had no DUI disposition in the prior five years and whose offense did not involve a death or serious injury. Repeat offenders generally cannot get an MDDP and instead face a longer Restricted Driving Permit process that also requires a BAIID. The driver pays for installation and monthly monitoring.

License suspension and the statutory summary suspension in Illinois

Illinois runs two systems at once. The statutory summary suspension under 625 ILCS 5/11-501.1 is an automatic administrative action by the Secretary of State based on the test result, independent of the criminal court outcome. For a first offender, failing the chemical test (0.08 percent or more) brings a six-month suspension, and refusing the test brings a 12-month suspension; the suspension takes effect on the 46th day after the notice of suspension. A repeat offender faces longer summary suspensions. Separately, a criminal DUI conviction triggers a mandatory license revocation of at least one year under 625 ILCS 5/6-208.1, and because a revocation is not a fixed term, the driver must apply for reinstatement and prove fitness to drive rather than simply waiting it out.

Repeat offenses and the Illinois look-back period

Illinois treats prior DUIs harshly because, for criminal felony enhancement, there is no washout period: prior DUI dispositions count for life under 625 ILCS 5/11-501. The five-year window in Illinois matters mainly for first-offender benefits like court supervision and the MDDP, not for counting priors. A second DUI is a Class A misdemeanor with a mandatory minimum five days in jail or 240 hours of community service, and it triggers a five-year revocation. The felony threshold sits at the third offense: a third DUI is aggravated DUI, a Class 2 felony, and the conviction brings a 10-year revocation. A DUI that causes great bodily harm or permanent disability is a Class 4 felony aggravated DUI, and a DUI causing death is a Class 2 felony, both regardless of offense number.

Watch out: Refusing the chemical test does not protect your license. A first refusal triggers a 12-month statutory summary suspension, twice the six-month suspension for failing the test, and a driver who refuses generally is still eligible for an MDDP only under the suspension that the refusal creates.

Refusing a breath or blood test in Illinois

Illinois's implied consent law, in 625 ILCS 5/11-501.1, provides that by driving in the state you have agreed to chemical testing of breath, blood, or urine if lawfully arrested for DUI. Refusing the test triggers a 12-month statutory summary suspension on a first offense, twice the six-month suspension that follows failing the test, and a three-year suspension for a repeat refusal. The refusal can also be introduced as evidence in the criminal case. Because the refusal suspension is longer, refusing usually makes the license consequences worse, not better. The driver may challenge the summary suspension by filing a petition to rescind, which the court must hear within 30 days or at the first court date.

Can you expunge or seal a DUI in Illinois

Illinois does not allow a DUI conviction to be expunged or sealed. Under the state's expungement and sealing law, a DUI is specifically carved out, so a conviction stays on the criminal record and on the Secretary of State driving record permanently, and it cannot be removed even if it was later reduced. Court supervision, while it avoids a conviction, also cannot be expunged for a DUI; supervision for a DUI remains on the driving record for life and counts against first-offender eligibility in the future. The only records that can be cleared are arrests or charges that did not lead to a conviction or supervision, such as a DUI that was dismissed or resulted in an acquittal. Anyone seeking to clear a non-conviction DUI record should confirm eligibility with the circuit court.

What to do after a DUI arrest in Illinois

An Illinois DUI creates two separate matters: a criminal case in the circuit court and an administrative license case with the Secretary of State. The deadlines are short, so a common first step is to file a petition to rescind the statutory summary suspension before it takes effect on the 46th day after notice, because the suspension is automatic otherwise. 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 facts, the evidence, and your record. Many people consult a licensed Illinois DUI attorney to understand the charge, the summary-suspension deadline, and the options for both the criminal case and the license case. Keep the arrest paperwork, the notice of summary suspension, and any test results in a safe place.