Illinois CDL Study Guide
Illinois issues commercial driver licenses (CDLs) through the Office of the Illinois Secretary of State. The process starts with a Commercial Learner's Permit (CLP), includes federal Entry-Level Driver Training, and ends with a three-part skills test. You can schedule CDL exams online with the Illinois Fast Pass system.
Key Illinois numbers
- Minimum age (intrastate): 18
- Minimum age (interstate or hazmat): 21
- CLP hold before skills test: at least 14 days
- General Knowledge passing score: 80%
- General Knowledge test: ~50 questions
- Air Brakes test: ~25 questions (required if your vehicle has air brakes)
- Combination Vehicles test: ~20 questions (required for Class A)
Topics on the Illinois General Knowledge test
- Vehicle inspection (pre-trip, en-route, post-trip)
- Driving safely (speed management, space management, hazard perception)
- Transporting cargo safely
- Air brakes (if your vehicle is air-braked)
- Combination vehicles (Class A)
If you fail a test
Illinois sets retake rules for failed CDL knowledge and skills tests. Applicants must usually wait before retesting and may pay test fees again. Specific wait times are published in the Illinois CDL Study Guide and at CDL testing facilities.
Frequently asked questions
How old do I have to be to get an Illinois CDL?
You must be at least 18 to get an Illinois CDL for driving inside Illinois. You must be 21 to drive across state lines or carry hazardous materials.
How long do I have to hold the Illinois CLP?
You must hold the Commercial Learneru0027s Permit for at least 14 days before you can take the CDL skills test.
What does an Illinois CDL cost?
The Illinois Secretary of State charges $50 for the Commercial Learneru0027s Permit and $60 for the CDL.
Do I need ELDT in Illinois?
Yes. You must finish federal Entry-Level Driver Training with an FMCSA-registered provider before scheduling the CDL skills test.
How do I schedule an Illinois CDL skills test?
Use the Illinois Fast Pass system at ilsos.gov. It lets you book pre-trip, basic control, and on-road exams 24/7.
Where do I find the Illinois CDL Study Guide?
The Illinois CDL Study Guide is available as a free PDF on the Illinois Secretary of State website at ilsos.gov.
Free practice
Start an Illinois General Knowledge quiz →
Sources: Illinois CDL Study Guide (DSD CDL 10) Illinois SOS CDL Overview Illinois SOS ELDT page Illinois SOS Fees