Illinois BAC Information

Blood-Alcohol Content (BAC) BAC is a measurement of the amount of alcohol in your system based on a test of your breath, blood or urine.

It is illegal to drive if your BAC is .08% or more. However, you can be convicted of a DUI if your BAC is less than .08% and your driving ability is impaired.

Your BAC is determined primarily by two factors: how much alcohol you drink and how much time passes between drinks. Other contributing factors include gender, body weight, alcohol tolerance, mood, environment and the amount of food consumed. From your first drink, alcohol affects your coordination and judgment.

Even with a BAC well below .08%, your reaction time slows. Your risk of being in a crash begins to climb with a BAC between .04% and .05% and increases rapidly after that. By the time you reach a BAC of .06%, you are twice as likely to be involved in a fatal crash as a non-drinking driver.

By the time you reach a BAC of .08%, you are 11 times more likely to be killed in a single-vehicle crash than a non-drinking driver.

The only way to rid the body of alcohol is time. Fresh air, coffee, a shower and food cannot change your BAC or make you sober. It takes about one hour for the body to metabolize one drink.

Each of the following has a comparable amount of alcohol and counts as one drink: one 12-ounce mug of beer, one 5-ounce glass of wine or one 1.5-ounce shot of hard liquor. (The amount of alcohol in a poured/mixed drink is dependent on the type of drink and the person who pours it.)

This information is from Illinois 2023 DUI Fact Book