What you need to do to get a CDL

Getting a Commercial Driver's License (CDL) requires passing a written knowledge test, a skills test, and a medical examination. You must be at least 18 years old to drive a commercial vehicle intrastate (within your state) and 21 to drive interstate. The process takes weeks to months depending on how quickly you study, schedule tests, and find a testing location.

Your state's Department of Motor Vehicles (DMV) or equivalent agency administers the CDL program. You start by getting a Commercial Learner's Permit (CLP), which lets you practice driving a commercial vehicle with a licensed CDL holder in the passenger seat. After holding the CLP for a set period (usually 14 days minimum, though some states require longer), you can take the skills test.

The entire sequence — permit process, studying, knowledge test, waiting period, skills test, and final CDL issuance — typically takes 4 to 12 weeks. Some people complete it faster if they study intensively and book tests when ready; others take longer if testing slots fill up or they need multiple attempts.

Key Takeaways

  • You must pass a medical exam, a written knowledge test covering traffic laws and vehicle operation, and a practical driving skills test before the DMV issues your CDL.
  • Most states require you to hold a Commercial Learner's Permit for at least 14 days before you can take the skills test, so plan for at least a month total.
  • The knowledge test covers general CDL rules plus endorsement-specific material if you want to haul hazmat, doubles, or tank vehicles.
  • You must bring proof of identity, Social Security number, residency, and medical certification to your DMV appointment.
  • Some states allow you to take the knowledge test at a third-party testing center, which may have more available dates than your local DMV.

The medical exam and certification

Before you can get a CLP, you must pass a Department of Transportation (DOT) medical examination performed by a certified medical examiner. This is not your regular doctor's checkup — it is a specific physical that checks your vision, hearing, blood pressure, and ability to operate a commercial vehicle safely. The exam costs between $50 and $200 depending on the examiner and your location.

The examiner will ask about your medical history, including any conditions that might affect driving — diabetes, heart problems, sleep apnea, or medications that cause drowsiness. If you have a condition that requires monitoring, the examiner may issue a certificate with restrictions or a shorter validity period. You receive a Medical Examiner's Certificate (also called a DOT medical card) that is valid for two years.

You must bring this certificate to your DMV appointment when you explore for the CLP. Without it, the DMV will not issue your permit. If your certificate expires while you hold a CDL, you must renew it before you can legally drive a commercial vehicle.

Knowledge test content and study materials

The CDL knowledge test has two parts: the general knowledge test and tests for any endorsements you want (hazmat, doubles, tank vehicles, and so on). The general test covers traffic laws, vehicle inspection, safe driving practices, and what to do in emergencies. Most states allow you 60 minutes to answer 50 questions; you typically need a score of 80 percent or higher to pass.

Each endorsement has its own test. If you want to haul hazardous materials, you take the hazmat test, which covers how to identify hazmat, load it safely, and handle spills. Tank vehicle endorsement tests cover the physics of liquid sloshing and how to brake and turn safely with a tank. You can take endorsement tests at the same appointment as your general test or at separate visits.

Your state DMV publishes a CDL handbook (free, online or in print) that covers all test material. Many people also use third-party study guides, practice tests, and apps — these are not required, but they help you pass on the first try. Some truck driving schools provide study materials as part of their programs.

The Commercial Learner's Permit waiting period

After you pass the knowledge test and receive your CLP, you must wait before taking the skills test. Most states require a minimum of 14 days; a few require 7 days, and some require 30 days or more. During this time, you can practice driving a commercial vehicle with a licensed CDL holder (usually a trainer or experienced driver) in the vehicle with you.

This waiting period exists so you have time to practice and become comfortable with the vehicle before the examiner watches you drive. Many people use this time to attend a truck driving school, which provides both the practice and the instruction. Others practice with a friend or family member who holds a CDL.

You cannot legally drive a commercial vehicle for pay during the CLP phase — the permit is for practice only. Once you pass the skills test and receive your CDL, you can drive commercially.

The skills test: what the examiner watches

The CDL skills test has three parts: vehicle inspection, basic control, and road test. The entire test takes 1 to 2 hours. You must bring your own commercial vehicle (or use one provided by a testing center or school) and a licensed CDL holder to supervise.

In the vehicle inspection portion, you walk around and inside the truck, pointing out safety equipment and explaining what you check before driving — lights, brakes, tires, mirrors, coupling devices, and so on. The examiner is not looking for a perfect vehicle; they are checking whether you know what to look for and why it matters.

The basic control test happens in a closed course or parking lot. You perform backing maneuvers, lane changes, and turns while the examiner watches from the passenger seat. You must stay within marked boundaries and show smooth, controlled movements.

The road test is a 20- to 30-minute drive on public roads. The examiner watches how you accelerate, brake, turn, merge, and handle traffic. They are assessing whether you can operate the vehicle safely and follow traffic laws. If you fail any of the three parts, you can retake that part (rules vary by state) without retaking the entire test.

Costs and timeline

The total cost of getting a CDL ranges from $300 to $2,000 or more, depending on whether you attend a formal truck driving school. Here is what you typically pay:

  • Medical exam: $50 to $200
  • CLP process and knowledge test: $50 to $150 (varies by state)
  • Skills test: $100 to $300 (varies by state and whether you use a third-party tester)
  • CDL license issuance: $50 to $200 (varies by state)
  • Truck driving school (optional but common): $3,500 to $15,000 for a 4- to 8-week program

If you do not attend a formal school, you can study on your own using the DMV handbook and practice tests, then schedule your tests directly with your state DMV. This route costs less but requires you to find a commercial vehicle to practice and test with, and you must arrange your own instruction.

The timeline without school is typically 4 to 8 weeks: 1 to 2 weeks to study and schedule the knowledge test, 1 to 2 weeks for the test appointment, 2 to 4 weeks waiting for the CLP period to end, 1 to 2 weeks to schedule and take the skills test, and 1 to 2 weeks for the DMV to issue your license. With school, the timeline is usually 4 to 8 weeks for the school program itself, plus 1 to 2 weeks for the skills test and license issuance.

State-by-state differences

CDL rules are set by federal law, but states handle testing, fees, and some procedural details differently. Some states allow third-party testing centers (private companies authorized by the state) to administer the knowledge and skills tests, which can mean more available appointments. Other states require all testing at the DMV.

CLP waiting periods range from 7 to 30 days. Some states let you take multiple endorsement tests in one visit; others require separate appointments. Medical certificate validity periods are usually two years, but some states recognize shorter periods for certain conditions.

Before you start, check your state's DMV website for the specific rules, required documents, current fees, and testing locations. The process is similar everywhere, but the details matter when you are scheduling.

Frequently Asked Questions

Can I take the knowledge test online or at a testing center instead of the DMV?

Many states allow third-party testing centers to administer CDL knowledge tests, which often have more available dates than the DMV. Check your state DMV website to see if third-party testing is available in your area. The skills test must usually be taken at a DMV-approved location, though some states contract with private testing centers for that as well.

What happens if I fail the knowledge test or skills test?

You can retake the test. Most states let you retake the knowledge test when ready or within a few days. For the skills test, you usually can retake just the section you failed (backing, road test, etc.) without redoing the entire test. Check your state's rules on how many attempts you get and whether there is a waiting period between attempts.

Do I need to attend a truck driving school to get my CDL?

No. You can study on your own using the DMV handbook, pass the knowledge test, practice with a commercial vehicle and a licensed driver, and take the skills test without formal school. However, many employers prefer or require school attendance, and school provides structured instruction and a vehicle for testing, which makes the process easier.

Can I get a CDL if I have a medical condition?

It depends on the condition and how it is managed. The medical examiner will review your history and may issue a certificate with restrictions (for example, daylight driving only, or requiring corrective lenses). Some conditions disqualify you from interstate driving but not intrastate. Discuss any health concerns with the medical examiner before your appointment.

How long is a CDL valid?

A CDL is typically valid for four or eight years, depending on your state and whether you are a commercial driver or a non-commercial driver. Your medical certificate must be renewed every two years. If your medical certificate expires, your CDL becomes invalid until you renew it.