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Illinois · IL
Illinois CDL
Knowledge Test
Everything you need to pass the Illinois CDL knowledge test. The same FMCSA-standardized questions used across all 50 states.
Total CDL fee
$60
CLP wait
14 days
Min age
18+
To pass
80%
CDL Test Sections
The CDL knowledge test is administered by section. Passing score for all sections is 80%.
✓
General KnowledgeREQUIRED
50 questions · Pass with 40+
A
Air Brakes
25 questions · Pass with 20+
C
Combination Vehicles
20 questions · Pass with 16+
H
Hazardous Materials (HazMat)
30 questions · Pass with 24+
D
Doubles & Triples
20 questions · Pass with 16+
T
Tanker Vehicles
20 questions · Pass with 16+
P
Passenger Transport
20 questions · Pass with 16+
S
School Bus
20 questions · Pass with 16+
What to Know About CDL in Illinois
Illinois CDL fees: approximately $60 total (CLP + CDL)
Illinois is the 5th largest trucking state in the US
Chicago O'Hare and major rail yards create strong freight demand
Illinois requires a CDL skills test at an approved third-party testing site
The written knowledge test is computerized at Secretary of State facilities
Illinois CDL holders driving hazmat must register with FMCSA
Legal notice
This information is provided for educational purposes only. Requirements can change. Always verify with Illinois Secretary of State for the most current information.
How to Get Your CDL in Illinois
The steps to earn a commercial driver's license in Illinois, from your DOT medical card to your CDL.
- 1
Get your DOT medical card
Visit a certified medical examiner, pass the DOT physical, and keep the certificate on file with Illinois Secretary of State.
- 2
Study and pass the knowledge test
Cover General Knowledge plus any endorsements you need (Air Brakes, Combination, HazMat). Practice every section on Koydo until you're scoring 80%+.
- 3
Get your CLP
Pass the Illinois knowledge test at a Illinois Secretary of State Driver Services Facility and pay the ~$30 permit fee to receive your commercial learner's permit.
- 4
Hold your CLP for 14 days
Federal rules require a minimum 14-day wait while you practice driving with a licensed CDL holder.
- 5
Pass the skills test
Schedule the pre-trip inspection, basic control, and road test with Illinois Secretary of State (or an approved third-party tester).
- 6
Get your Illinois CDL
Pay the ~$30 CDL fee and you're licensed to drive commercially.
Illinois CDL — Frequently Asked Questions
How much does a CDL cost in Illinois?
Illinois CDL fees come to about $60 total — roughly $30 for the commercial learner's permit (CLP) and $30 for the CDL itself, paid at Illinois Secretary of State. Testing and endorsement fees can add to this, so always confirm current amounts with Illinois Secretary of State.
What score do I need to pass the Illinois CDL knowledge test?
You need 80% on each CDL knowledge section. Illinois uses the same FMCSA-standardized question pool as every other state, so General Knowledge, Air Brakes, Combination Vehicles, and the endorsement tests are federally consistent.
How old do I have to be to get a CDL in Illinois?
Illinois issues a CDL at 18 for driving within the state (intrastate) and 21 for driving across state lines (interstate) or hauling hazardous materials.
How long must I hold a CLP before the Illinois skills test?
At least 14 days. You pass the knowledge test first to earn your CLP, hold it for 14 days while practicing with a licensed CDL holder, then take the behind-the-wheel skills test.
Where do I take the CDL written test in Illinois?
At a Illinois Secretary of State Driver Services Facility. The knowledge test is computerized. Practice every section on Koydo before you go so you walk in ready.
Is the Koydo CDL practice test accurate for Illinois?
Yes. Koydo's questions follow the FMCSA CDL standard that Illinois tests on, plus state-rule practice — with no ads, and your first 15 questions a day are free.
Ready to get your CDL in Illinois?
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