Illinois CDL Practice Test and Test Prep (2026)
Illinois gives CDL tests through Illinois Secretary of State — Driver Services Department (Commercial Driver's License Section). Here is what you will be tested on, which of our practice quizzes match each test, and what the skills test involves in Illinois.
Knowledge tests for a Illinois permit
- Basic written test (all applicants)
- Core Knowledge / General Knowledge (all applicants) — practice General Knowledge (60 questions)
- Combination Vehicles (Class A) — practice Combination Vehicles (30 questions)
- Air Brakes (if the vehicle you test in has them) — practice Air Brakes (40 questions)
- Any endorsement tests you need (P, S, H, N, T)
Permit minimum age: 18 (in-state driving) or 21 (interstate). Holding period before the skills test: 14 days. Permit validity: confirm with the agency.
Illinois endorsement tests and practice
- Hazmat (H) practice
Illinois notes for this endorsement
Hazardous materials. Illinois is NOT a TSA self-managed state, so you use the standard TSA HazMat Threat Assessment Program through the Universal Enrollment provider (IdentoGO/IDEMIA): pre-enroll with TSA, get fingerprinted at an IdentoGO center, and pass the security threat assessment before you can take the hazmat knowledge test. ELDT is required for first-timers. Issuance is prohibited until TSA approves.
- Tanker (N) practice
Illinois notes for this endorsement
Tank vehicles. No TSA background check; available with the tank knowledge test.
- Passenger (P) practice
Illinois notes for this endorsement
Passenger. Requires ELDT for first-timers plus a passenger knowledge and skills test; adding it to an existing CDL needs a fresh CLP and 14-day hold.
- School bus (S) practice
Illinois notes for this endorsement
School bus. Requires ELDT for first-timers, the passenger and school-bus knowledge tests, and a school-bus skills test. Cannot be obtained through the military skills-test waiver.
- Doubles/triples (T) practice
Illinois notes for this endorsement
Double/triple trailers. Knowledge test only; no skills test or TSA check.
The Illinois skills test
Components: Pre-Trip inspection, Basic Control Skills, On-road drive test.
Test vehicle: You must bring a representative vehicle of the proper class, with the proper equipment, for the CDL you want. The Secretary of State does not provide a test vehicle.
Where and how to book: Schedule the pre-trip, basic control, and road exams through Illinois Fast Pass online (24/7) at any Secretary of State CDL testing facility, or by phone at 217-785-3013 (Mon–Fri, 8 a.m.–4:30 p.m.). Illinois also runs a Third-Party Certification Program that lets approved companies (mainly trucking employers) and CLP third-party testers administer skills tests to their own trainees; program contact is 630-520-9310.
Waits and retests: Availability varies by facility; the Fast Pass system lets you book in advance, but you cannot select a test date inside the 14-day CLP hold. Popular Chicago-area facilities can book out further, which is part of why many drivers use employer or school third-party testers. Specific wait times are not published — check Fast Pass for live availability.
Practice the inspection part with our pre-trip inspection guide. Research dated 2026-07-20; confirm testing details with Illinois.
All practice tests
- General Knowledge (60 questions)
- Air Brakes (40 questions)
- Combination Vehicles (30 questions)
- Hazardous Materials (H) (30 questions)
- Tank Vehicles (N) (25 questions)
- Passenger (P) (25 questions)
- School Bus (S) (25 questions)
- Doubles/Triples (T) (20 questions)
Ready to apply? See the full Illinois CDL requirementsor build your Illinois checklist.