The knowledge test trips up many first-time applicants. Here's exactly what to study and how to walk in prepared.
The Illinois DMV knowledge test is 35 questions. You must score at least 80% to pass — meaning you need at least 28 correct and can miss up to 7.
If you fail, you can retake the test — three attempts are allowed within one year of paying the $20 permit fee, and many facilities let you retake the same day.
The written test is taken in person at a Secretary of State Driver Services facility. Most of the 44 busiest facilities require an appointment — schedule at ilsos.gov before you go.
Applicants under 18 must complete an approved driver education course (30 hours classroom plus 6 hours behind the wheel) before being fully licensed.
The legal BAC limit is .08% for drivers 21+, .04% for commercial drivers, and any trace (Zero Tolerance) under 21. Refusing a chemical test triggers a 12-month suspension.
A 1st DUI is a Class A misdemeanor: up to $2,500 fine, up to 1 year in jail, and a minimum 1-year revocation. Penalties climb with each offense; a 3rd DUI is a felony.
Instruction permit at 15 (with driver's ed), held 9 months with 50 hours of practice (10 at night) and a licensed adult 21+ in the front seat. Provisional license at 16 with a 10 PM/11 PM curfew and a one-passenger-under-20 limit.
Use the 3-second following rule, and add more seconds at higher speeds or in rain, fog, and snow.
Urban districts default to 30 mph, school zones 20 mph, alleys 15 mph, rural highways 55 mph, and interstates/tollways up to 70 mph. The posted sign is always the maximum.
Signal at least 100 feet before turning in the city (200 feet outside city limits). Right on red is allowed after a complete stop unless posted; left on red only from a one-way onto a one-way.
Stop at least 20 feet from a school bus with flashing red lights — both directions on a two-lane road. The only exception: oncoming traffic on a roadway of four or more lanes.
Headlights are required sunset to sunrise and whenever wipers are on. Dim high beams within 500 ft of an oncoming vehicle and within 300 ft when following another vehicle; use low beams in fog, rain, or snow.
Fire hydrant 15 ft, crosswalk 20 ft, fire station driveway 20 ft, stop sign/signal 30 ft, railroad crossing 50 ft. When parallel parking, finish within 12 inches of the curb.
Children under 8 need a child safety seat or booster; children under 2 must be rear-facing (unless over 40 lb or 40 in). All occupants must wear a seat belt — primary enforcement.
You need 80% (28 of 35) to pass — but aim for 90%+ on the simulator before you go, so test-day nerves don't cost you.
Memorize BAC limits, distances, signal distance, following distances, and suspension periods. These specific numbers appear on virtually every Illinois test.
The Weak Spots mode saves every question you got wrong. Replay it until you're hitting 90%+ before going to the DMV office.
Download the Illinois Rules of the Road at https://www.ilsos.gov/. Every question comes directly from this manual.
Illinois interstates and tollways top out at 70 mph, but the urban-district default is just 30 mph and alleys are 15 mph — watch for the change as you enter a town.
Sign questions are visual — shape, color, and meaning all matter. Use the Road Signs Quiz mode to practice all signs before test day.
Free, no signup · Questions verified against the official state driver manual