CDL Frequently Asked Questions
From eligibility requirements to the exam process, from fees to career prospects — we've compiled the questions test-takers ask most often while preparing for the CDL commercial driver's license, along with clear, accurate answers.
Eligibility
Can I apply for a CDL at 18?
Yes, but with restrictions. Applicants aged 18 to 20 may only drive commercial vehicles intrastate (within the state that issued the license). You must be at least 21 years old to drive interstate (across state lines) or to transport hazardous materials or hazardous waste.
Can I hold a CDL from more than one state at the same time?
No. Federal law strictly prohibits holding more than one commercial driver's license at a time. If you move to a new state, you must transfer your CDL within the required timeframe — check the current requirements of the state you're moving to.
Can I apply for a CDL without a California regular driver's license?
No. Applicants must first hold a valid California non-commercial Class C license (a permit is also accepted) before applying for a CLP and then a full CDL.
Can green card or work visa holders apply for a CDL?
Yes, as long as you can provide the proof of lawful residence required by federal law, you can apply for a standard CDL. However, if you plan to add a Hazmat (H) endorsement, you must be a lawful permanent resident of the U.S. and pass a TSA fingerprint-based background check.
Can I take the CDL exam if my English isn't strong?
The knowledge test itself is available in several languages in most states. However, federal regulations require commercial drivers to have basic English communication and comprehension skills for reading road signs, filling out reports, and communicating with law enforcement and shippers. The skills/road test is typically conducted in English.
Exam Process
Can I take the official CDL exam online?
No. While online practice platforms are excellent for preparation, the official knowledge test and skills test must be taken in person at a state-run DMV location or an authorized third-party testing center.
How many attempts do I get for the knowledge test and skills test?
Each application allows up to 3 attempts at the knowledge test. The skills test — vehicle inspection, basic control skills, and the on-road driving test — also allows a combined total of 3 attempts across all three parts; failing any single part counts toward the total. Once you use up your attempts, you must submit a new application and pay the fees again.
How long after getting my CLP can I take the road test?
After obtaining your CLP (Commercial Learner's Permit), you must wait at least 14 days before scheduling the skills test (road test). The same waiting period applies when upgrading your vehicle class or adding new endorsements/restrictions.
What does the road test actually cover?
The road test has three parts: the vehicle inspection test (about 40 minutes, explaining what to check on each part of the vehicle and why), the basic control skills test (about 30 minutes, covering maneuvers like backing up and turning in a controlled area), and the on-road driving test (about 45–60 minutes, evaluating your driving skills in real traffic conditions).
Do I use my own vehicle or the driving school's vehicle for the test?
The skills test must be taken in a commercial vehicle that meets the standards for the license class you're applying for. Most test-takers use a training vehicle provided by their driving school. If you use an employer-owned or personal vehicle, make sure it meets the DMV's inspection requirements for that class.
Fees & Timeline
How much does it cost to get a CDL in 2026?
Total costs generally range from $1,500 to $8,000, depending on your state DMV's administrative fees and whether you enroll in an ELDT-certified professional truck driving school program. The DMV's own original application fee is $82, and renewal is $48.
How long does it take to get a CDL?
Getting a full commercial license typically takes 4 to 7 weeks of intensive training, including classroom theory, online/in-person ELDT coursework, and hands-on training for backing maneuvers and basic road skills. The actual timeline varies based on your personal schedule and the driving school's availability.
How often do I need to renew my CDL?
A California CDL is valid for up to 5 years, with the exact expiration date tied to your birthday. Drivers who operate interstate must also renew their federal medical certificate annually and submit it to the DMV for their record, or their license status could be downgraded.
Is there an extra fee for retaking the test?
Yes. A retest fee of $37 applies for a repeat skills test or road test. If you use up all 3 attempts at the knowledge test or the skills test, you'll need to submit a brand-new application and pay the original application fee again.
Endorsements & Restriction Codes
What is the CDL automatic transmission restriction (Restriction E)?
If you take your official DMV road test in a truck equipped with an automatic transmission, the DMV will mark "Restriction E" on your license, which legally prohibits you from driving a manual-transmission commercial truck. To remove this restriction, you must retake and pass the skills test in a manual-transmission vehicle.
What's the relationship between the H, N, and X endorsements?
The H endorsement corresponds to the hazardous materials knowledge test, and the N endorsement corresponds to the tank vehicle knowledge test. When a driver passes both the H and N tests, the system automatically issues the combined X endorsement, used for interstate transport of high-value liquid hazardous material fleets.
Do I need to pass the Passenger endorsement before I can get a School Bus endorsement?
Yes. Applying for the School Bus (S) endorsement requires that you've already passed the Passenger (P) test, which covers all the basic safety procedures that build toward it — the two are sequential in content.
What does Restriction L mean?
If you don't take or pass the air brakes knowledge test, or if the vehicle you use for your skills test doesn't have air brakes, the DMV will mark your license with Restriction L, prohibiting you from driving commercial vehicles equipped with air brakes. This is a common oversight that ends up limiting many test-takers' job opportunities.
Medical & Compliance
Do I need to see a specific doctor for the medical exam?
Yes. The exam must be performed and the MER/MEC form signed by a physician listed on the federal National Registry of Certified Medical Examiners. Certificates from a regular family doctor are not accepted.
Can I still get a CDL if I have a chronic condition?
Some chronic conditions (such as well-controlled diabetes or high blood pressure) can still pass the medical exam if they meet federal standards and are approved by a certified medical examiner. Whether you qualify is decided case-by-case according to federal medical standards, so it's best to consult a certified medical examiner ahead of time.
What happens if I'm caught driving under the influence?
The blood alcohol standard for commercial drivers is far stricter than for regular drivers: a BAC of 0.04% or higher is a violation. A first offense results in CDL disqualification for at least 1 year, and if you were transporting hazardous materials, a first offense results in a 3-year disqualification.
Employment & State Transfers
Is my CDL still valid after I move to another state?
Federal law requires each driver to hold only one commercial driver's license. After moving to a new state, you must transfer to a local CDL at the new state's DMV within the required timeframe — check the latest rules for the state you're moving to.
Is it easy to find a job right after getting my CDL?
Many trucking companies set minimum experience requirements for new drivers (some insurers require at least 1–2 years of driving experience). Completing an ELDT-certified course and choosing a company that offers paid apprenticeships or mentor-led programs generally makes it easier to land your first long-haul or local driving job.
Which is easier to find work with, Class A or Class B?
The two lead to different career paths: Class A covers a broader range of jobs, suited to long-haul trucking, flatbeds, and other interstate roles; Class B is more focused on local delivery, concrete mixers, school buses, and other single heavy-vehicle roles. Your choice should be based on the type of work you want, not simply which is "easier."
Does a Hazmat endorsement increase my pay?
Specialized jobs like hazardous materials transport and tanker driving typically offer more competitive pay due to the higher technical requirements and responsibility involved. However, they also come with a TSA background check, stricter compliance record requirements, and harsher penalties for alcohol violations.
Didn't find your answer? Jump into practice tests to fill in the gaps
If this page didn't answer your question, feel free to let us know through the feedback form in the footer — we update this FAQ page regularly. In the meantime, we recommend diving into a practice test to reinforce what you've learned.