Iowa CDL Practice Tests

Iowa (IA) drivers preparing for a CDL permit can use these five practice questions to review essential knowledge areas covered on the Commercial Learner’s Permit (CLP) exam.

Iowa CDL Practice Tests: General Knowledge, Combination Vehicle & Air Brakes

Drivers preparing for an Iowa Commercial Driver’s License (CDL) should focus on three essential CDL practice tests. These align with the written knowledge exams required by the Iowa Department of Transportation (Iowa DOT) and help reinforce key concepts tested on the official CDL exam.

• General Knowledge CDL Practice Test
• Combination Vehicle CDL Practice Test
• Air Brakes CDL Practice Test

Pair these practice tests with the Iowa CDL manual to improve comprehension and build confidence ahead of your official written exams. The Iowa CDL manual corresponds to the knowledge sections tested at Iowa DOT service centers.

Preparing for the Iowa CDL Exam

Commercial driver licensing standards are established at the federal level by the Federal Motor Carrier Safety Administration (FMCSA). Each state administers its own CDL testing and licensing.

In Iowa, CDL tests and licensing are managed by the Iowa Department of Transportation (Iowa DOT). The official Iowa CDL manual is published by the Iowa DOT and should be reviewed before testing:

• Iowa CDL Manual (PDF)

The Iowa CDL manual applies to all commercial license classes, including:

• Class A CDL
• Class B CDL
• Class C CDL

Iowa CDL Eligibility Requirements

Age Requirements:
You must be at least 18 years old to obtain a CDL for intrastate (Iowa-only) driving. To operate interstate or transport hazardous materials, you must be at least 21 years old.

Valid Iowa Driver’s License

You must hold a valid Iowa non-commercial driver’s license before applying for a Commercial Learner Permit (CLP) or CDL.

Medical Certification

All Iowa CDL applicants must meet FMCSA medical certification requirements, including passing a DOT physical with an approved medical examiner listed on the FMCSA National Registry.

FMCSA medical certification requirements

CDL Knowledge Tests and Endorsements

Applicants must pass written knowledge tests covering general CDL topics, air brakes (if applicable), and any endorsements for their intended type of commercial driving.

Common CDL endorsements include:

• Hazardous Materials (H)
• Tank Vehicles (N)
• Passenger (P)
• School Bus (S)

Entry-Level Driver Training (ELDT)

Federal Entry-Level Driver Training (ELDT) requirements apply to many Iowa CDL applicants. ELDT includes classroom instruction and behind-the-wheel training through an FMCSA-registered training provider before testing.

FMCSA Training Provider Registry

Background Checks

Certain endorsements, such as Hazardous Materials, require a federal background check, which includes fingerprinting and TSA vetting. Applicants must also provide documentation verifying identity, Iowa residency, and lawful presence.

Iowa CDL Application Process

To obtain a CDL in Iowa, applicants must:

• Submit a CDL application at an Iowa DOT service center.
• Pass the required written knowledge exams to obtain a Commercial Learner Permit (CLP).
• Hold the CLP for the required period before skills testing (as outlined by federal rules).
• Complete any required ELDT training.
• Pass the CDL skills exam, including vehicle inspection, basic skills, and road test.

Iowa CDL information and application steps

Iowa CDL Fees

Iowa CDL fees vary depending on the type of transaction (permit vs license), driver’s age, and whether endorsements are added. The fees below are based on the current Iowa DOT fee schedule and may change:

• Commercial Learner Permit (CLP): $45*
• First CDL Issuance: $90 (includes license issuance)
• CDL Renewal: $60
• Endorsement Knowledge Test: Additional exam fees may apply
• Hazardous Materials Background Check: Federal TSA fee (varies)

*Some Iowa DOT service centers may charge additional administrative or processing fees — applicants should confirm costs before applying.

View the official Iowa DOT fee schedule