What a Class B CDL lets you drive
A Class B Commercial Driver's License lets you drive a single vehicle weighing more than 26,001 pounds — like a straight truck, dump truck, or city bus — without towing a trailer. If you want to tow a trailer, you need a Class A instead. A Class B is the middle tier: heavier than a regular license allows, but not as heavy-duty as Class A.
You'll need a Class B if your job involves driving a box truck for deliveries, operating a cement mixer, driving a school bus, or hauling cargo in a single large vehicle. The license proves you've passed knowledge tests and a driving test specific to these bigger vehicles.
Key Takeaways
- You must be at least 18 years old (or 21 in some states for interstate driving) and hold a valid regular driver's license before you can get a Class B CDL.
- The process involves getting a Commercial Learner's Permit first, passing written tests on general CDL knowledge and air brakes, then passing a behind-the-wheel driving test.
- You'll need to provide documents like your Social Security number, proof of residency, medical certification, and a valid passport or birth certificate at your state's DMV.
- The entire process typically takes several weeks to a few months, depending on how quickly you study, schedule tests, and find a vehicle to test in.
- Some states require you to hold your learner's permit for a minimum waiting period before you can take the driving test.
Age and license requirements before you start
You must be at least 18 years old to get a Class B CDL in most states. However, if you plan to drive across state lines, federal rules require you to be 21. Some states set their own minimum at 21 even for in-state driving, so check your state's DMV website first.
You also need a valid regular driver's license (Class D or equivalent) before you can even explore for a CDL. If your regular license is suspended or revoked, you cannot get a CDL until it's restored. Your driving record matters — serious violations like DUIs or reckless driving can disqualify you or delay approval.
Getting your Commercial Learner's Permit
The first step is to visit your state's DMV and request a Commercial Learner's Permit, sometimes called a CLP. You'll fill out an process (usually Form CDLA or similar, depending on your state) and provide documents: your Social Security number, proof of residency (utility bill, lease, or bank statement), your valid regular driver's license, and a medical certification form signed by a doctor.
The medical certification is important — the doctor checks your vision, hearing, blood pressure, and overall fitness to operate a commercial vehicle. You'll need to pass this exam before the DMV will issue your permit. Some DMV offices have approved medical examiners on-site; others give you a list to choose from.
Once you have your permit, you can practice driving a Class B vehicle with a licensed CDL holder in the passenger seat. You cannot drive alone, and you cannot drive at night in most states — the permit has restrictions printed on it.
Passing the written knowledge tests
Before you take the driving test, you must pass two written tests at the DMV: the General Knowledge test and the Air Brakes test. Both are multiple-choice, taken on a computer or on paper depending on your state's setup.
The General Knowledge test covers vehicle inspection, basic control, safe driving practices, and cargo handling — about 50 questions, and you typically need 80% to pass. The Air Brakes test is shorter (about 25 questions) and focuses on how air brake systems work, since Class B vehicles use them. You need 80% on this one too.
You can take these tests the same day you get your permit, or wait until you feel ready. Many people study for a week or two using the CDL manual your state provides free at the DMV or online. Some states offer practice tests on their DMV website. You can retake either test if you fail, though there may be a fee and a waiting period between attempts.
Scheduling and passing the driving test
Once you've passed both written tests, you can schedule your behind-the-wheel driving test with the DMV. Some states require you to wait a certain number of days after getting your permit — check your state's rules. The test usually takes 30 to 45 minutes and covers vehicle inspection, basic control maneuvers (backing, turning, parking), and on-road driving.
You must bring a Class B vehicle to the test — your own, a friend's, or a rental. The vehicle must be in safe working condition and match the class you're testing for. You'll also bring your Commercial Learner's Permit, a valid ID, and proof of insurance for the vehicle.
The examiner will watch you perform a pre-trip inspection (checking lights, brakes, mirrors, and tires), then drive you through a route that includes residential streets, highways, and turns. They're looking for smooth steering, proper mirror checks, safe following distance, and correct use of signals and brakes. If you fail, you can retake it after a waiting period, usually 7 to 14 days.
Documents you'll need at each step
| Stage | Documents Needed |
|---|---|
| explore for Commercial Learner's Permit | Valid regular driver's license, Social Security number, proof of residency, medical certification form (signed by approved doctor), passport or birth certificate |
| Taking written tests | Commercial Learner's Permit, valid ID |
| Taking driving test | Commercial Learner's Permit, valid ID, proof of insurance for the test vehicle, the Class B vehicle itself |
| Getting your CDL card | Passing score on driving test; DMV issues the card |
Timeline and costs
The entire process usually takes 4 to 12 weeks, depending on how fast you study and how quickly you can schedule tests. Getting the medical certification might take a week or two if your doctor's office is busy. Written tests can often be scheduled within days. The driving test wait can be longer — some states have a backlog and book tests weeks out.
Costs vary by state. A Commercial Learner's Permit typically costs $10 to $50. Each written test might cost $10 to $20. The driving test usually costs $50 to $100. Your medical certification exam costs $50 to $150 depending on the doctor. If you need to retake any test, you'll pay the fee again. Renting a vehicle for the driving test can cost $50 to $200 depending on the truck rental company and your location.
Frequently Asked Questions
Can I use my own truck for the driving test if it's not registered to me?
Yes, as long as the truck is insured and in safe condition. The vehicle doesn't have to be registered in your name — it can belong to a friend, family member, or employer. You'll need proof of insurance showing the vehicle is covered. The examiner will inspect it before the test starts.
What happens if I fail the driving test?
You can retake it after a waiting period, usually 7 to 14 days depending on your state. You'll pay the test fee again. Your Commercial Learner's Permit stays valid while you practice more and schedule another attempt. There's no limit to how many times you can retake it, though some states may have rules about how many attempts you can make in a certain time frame.
Do I need to take a CDL training course?
No, it's not required by law in most states. You can study the manual on your own and practice with someone who holds a CDL. However, many people find a professional CDL training school helpful because instructors teach you the test route, help you understand air brakes, and provide a vehicle for practice. Some employers will pay for training if you commit to working for them afterward.
What's the difference between a Class B and Class A CDL?
A Class A lets you drive heavier vehicles and tow trailers; a Class B is for single heavy vehicles without a trailer. If your job might involve towing later, getting a Class A gives you more options, though the testing is slightly more complex.
Can I get a CDL if I have a DUI on my record?
It depends on how recent it is and your state's rules. A DUI within the last 3 to 5 years may disqualify you or delay approval. Contact your state's DMV directly — they'll review your specific record and tell you whether you're may be able to access.