Illinois CDL practice tests
762 free questions across 8 tests, every answer explained. The material is federal, so it is valid for Illinois Secretary of State exactly as it is everywhere else.
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General Knowledge
Required for every CDL applicant, whatever class or endorsement you're after. The longest and most-weighted test in the battery.
2Air Brakes
Required if the vehicle you'll drive has air brakes. Score under 80% and an air-brake restriction goes on your license.
3Combination Vehicles
Required for Class A. Coupling, uncoupling, trailer brakes and rollover prevention.
4Hazardous Materials (H)
Placarding, shipping papers, loading rules and emergency response for hazardous loads.
5Tank Vehicles (N)
Surge, baffles, bulkheads and the handling problems of a high centre of gravity.
6Passenger (P)
Loading, standee lines, emergency exits and passenger supervision.
7School Bus (S)
Danger zones, loading and unloading, evacuation and the mirror-check routine.
8Doubles & Triples (T)
Coupling order, converter dollies, and why rearward amplification makes trailers crack the whip.
What Illinois Secretary of State controls, and what it doesn't
This is the part most guides get wrong, and it decides how you should study.
| Set federally — same in all 50 states | Set by Illinois Secretary of State |
|---|---|
| The knowledge areas you are tested on | How many questions each test contains |
| The 80% passing score | The exact wording of its questions |
| Which endorsements exist (H, N, P, S, T) | Where and when you can sit the test |
| ELDT training requirements | Whether third-party testers are used |
| The 14-day commercial learner's permit hold | Retest waiting periods |
| Disqualification rules and the 0.04% BAC limit | Fees and appointment booking |
Practical consequence: nobody can sell you "the real Illinois CDL questions." The federal pool is not public, Illinois Secretary of State develops its own wording from it, and versions rotate. Any site claiming otherwise is describing something that does not exist.
Getting your Illinois CDL
- Complete ELDT first if you are a first-time Class A/B applicant or want H, P or S. Registered providers only.
- Pass the knowledge tests — General Knowledge plus whichever apply to your vehicle and cargo.
- Hold your commercial learner's permit for 14 days before the skills test. Federal minimum.
- Pass the skills test — pre-trip inspection, basic control, and the road test, in that order.
- Keep a valid medical certificate. Letting it lapse can downgrade your CDL automatically.
Illinois Secretary of State handles scheduling, fees and documents. Their official site is the authority on all of it.
Common questions
Is the CDL test different in Illinois?
The subject matter is not. CDL knowledge testing is federally governed — 49 CFR 383.111 prescribes the knowledge areas and 383.135 sets the passing score at 80% in every state. What Illinois controls is the wording of its questions and how many it asks. That is why studying by knowledge area works here exactly as it does anywhere else.
What passing score does Illinois Secretary of State require?
80% — and so does every other state. Unlike the Illinois car permit test, where the passing score is set locally, the CDL figure is federal and Illinois Secretary of State cannot set a different one.
How many questions will Illinois Secretary of State ask?
Test length is one of the few things states do vary, within the federal framework. Confirm the current count with Illinois Secretary of State — we would rather send you to them than print a number that may be out of date.
Do I need Entry-Level Driver Training in Illinois?
Yes, if you are a first-time applicant for a Class A or B CDL, or for the hazmat, passenger or school bus endorsements. ELDT is federal, so it applies in Illinois identically, and it must come from a provider on the FMCSA Training Provider Registry. This site cannot satisfy that requirement — study here, train there.
How old do I have to be?
21 for interstate driving and for hazardous materials, federally. Most states including Illinois allow 18 for intrastate-only work, which appears as a restriction on the licence. Confirm your route's rules with Illinois Secretary of State.