Illinois Driver's Handbook, Section 6: Driving Under the Influence (DUI)
BAC and drug limits, cannabis, implied consent, statutory summary suspension, DUI penalties and drivers under 21.
Summary written by MyPermitExam from the official handbook, 2026. Not a copy of the handbook. Checked Oct 2026. Not affiliated with the DMV. Illinois Rules of the Road (DSD A 112)
Key rules
- The limit is .08% BAC (or 5 ng of THC per ml of blood); any trace of controlled drugs is illegal. p. 48
- Failing the test: six-month suspension; refusing it: one year (three years for repeat offenders). p. 49
- DUI convictions: one year, then five years (within 20 years), 10 years and lifetime. p. 50
- Under 21: any trace of alcohol means at least three months of suspension; a DUI means at least two years of revocation. p. 52