CDL Endorsements & Restrictions

In order to drive certain types of vehicles with a commercial driver's license (CDL), it may be necessary to add an endorsement or remove a restriction. In either case, additional testing and fees will be required.

CDL Endorsements

After you have satisfied the requirements for a Class A, B, or C commercial driver's license, you may also need to pass additional written and road driving tests to operate special types of commercial motor vehicles.

Below is a list of the federal endorsement codes you may need in addition to your CDL and what tests will be required by your state.

  • H Endorsement: Required for vehicles containing hazardous materials.
    • Requires a written knowledge test.
  • N Endorsement: Permits you to operate tank vehicles.
    • Requires an additional written knowledge test.
  • P Endorsement: Allows you to operate a vehicle that carries over a specified number of passengers (the exact number may depend on your state).
    • Requires written knowledge AND road skills tests.
  • S Endorsement: Permits the operation of a school bus.
    • Requires written knowledge AND road skills tests.
    • ALSO requires separate application forms, fees, and background checks. See our guide to passenger and school bus endorsements.
  • T Endorsement: Allows you to tow a double or triple trailer.
    • Requires an additional knowledge test.
  • X Endorsement: Combination endorsement for HAZMAT and tank vehicles.
    • Requires a written knowledge test.

Check with your state to determine the exact process required for adding an endorsement to your commercial driver license.

CDL Restrictions

A restriction placed on your commercial driver's license may keep you from operating certain types of vehicles.

Common federal CDL restriction codes are listed below:

  • E Restriction: Prohibits you from operating vehicles with a manual transmission.
    • Occurs when you take your skills test in a CMV with automatic transmission.
  • L Restriction: Prohibits operation of a vehicle containing a full air brake system.
    • Occurs if you:
      • Fail the Air Brakes Knowledge Test.
      • Incorrectly identify air brake system components.
      • Fail to properly conduct an air brakes system check.
      • Take the road skill test in a CMV lacking a full air brake system.
  • Z Restriction: Also prohibits you from driving a CMV with full air brakes.
    • Occurs if you tested in a vehicle with an air over hydraulic brake system.
  • M Restriction: Restricts you to operating a Class B or C passenger vehicle/school bus ONLY.
    • Occurs if you possess a Class A CDL, but earned your passenger/school bus endorsement driving a Class B vehicle.
  • N Restriction: Restricts you to operating a Class C passenger vehicle/school bus ONLY.
    • Occurs when you possess a Class B CDL, but earned your passenger/school bus endorsement driving a Class C vehicle.
  • Restriction: Prohibits you from driving any Class A vehicle that has a fifth wheel connection.
    • Occurs when you take your skills test in a CMV that has a non-fifth wheel connection, such as a pintle hook.
  • V Restriction: Indicates that a medical variance has been reported by the Federal Motor Carrier Safety Administration (FMCSA).
    • This may occur, for instance, if you have a vision or diabetic waiver issued by the FMCSA.

Depending on your state, there may be additional restriction codes that can be placed on your CDL license.

Removing a CDL Restriction

If you wish to remove a restriction from your CDL, you may be required to complete or provide:

  • Additional written knowledge tests.
  • Additional road skills tests.
    • This includes testing in a vehicle meeting the requirements indicated by the restriction.
  • Further medical evaluations.
  • Payment of additional fees.
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