The X endorsement lets you haul hazardous materials in a commercial vehicle

The X endorsement on a commercial driver's license (CDL) is a combination of two separate endorsements — the H endorsement (hazmat) and the T endorsement (double/triple trailers) — rolled into one. If you have an X, you can legally transport hazardous materials and pull double or triple trailers. Most drivers who need hazmat permission also need trailer combinations, so the X saves them from getting two endorsements separately.

You cannot get an X endorsement by itself. You must first pass the hazmat test (H) and the doubles/triples test (T), and the state will then issue you an X to show you hold both. Some drivers get H without T, or T without H — those combinations do not result in an X.

The X endorsement does not change how you drive or what vehicle you operate. It changes what cargo you are legally permitted to carry and what trailer configurations you can pull. Without it, you cannot haul hazmat loads even if your truck and training are otherwise ready.

Key Takeaways

  • The X endorsement is a combination of the H (hazmat) and T (doubles/triples) endorsements, not a separate credential.
  • You must pass both the hazmat knowledge test and the doubles/triples knowledge test to receive an X endorsement.
  • The hazmat test covers material classifications, placarding, documentation, and safety procedures; the doubles/triples test covers vehicle handling and coupling.
  • Most states require a hazmat background check and fingerprinting before you can take the hazmat test.
  • You will need to renew your hazmat portion every three years, while the doubles/triples portion renews with your regular CDL.

How the H and T endorsements combine into an X

When you pass the H test (hazmat) and the T test (doubles/triples), your state's DMV or equivalent agency prints an X on your CDL to indicate you hold both. The X is shorthand — it does not appear as a separate line item on your license the way H or T might if you held only one.

If you hold H but not T, your license shows only H. If you hold T but not H, your license shows only T. The X appears only when both are present. This matters because some employers require the X specifically, while others need only H or only T depending on the job.

What the hazmat (H) test covers

The hazmat test is a written knowledge exam administered by your state's DMV. It covers nine major areas: hazard classes and divisions, placarding and labeling, shipping papers and documentation, vehicle placarding and marking, loading and unloading procedures, emergency response and accident procedures, hazmat employee responsibilities, safety equipment and procedures, and transporting specific materials like explosives or radioactive substances.

The test typically has 30 questions, and you must score at least 80 percent to pass. You can study using the hazmat section of your state's CDL manual, which is free and available online from your state's DMV website. Many drivers also use third-party study guides or practice tests, though the official manual covers everything tested.

Before you can take the hazmat test, you must pass a Transportation Security Administration (TSA) background check. This includes fingerprinting, a criminal history review, and a check against federal watchlists. The process takes several weeks. You will pay a fee (usually $85 to $100, though amounts vary by state) and must explore through your state's DMV or a designated fingerprinting location.

What the doubles/triples (T) test covers

The doubles/triples test is also a written knowledge exam. It covers vehicle dimensions and weight limits, coupling and uncoupling procedures for double and triple trailers, inspecting doubles and triples, controlling the vehicle (braking, turning, backing), and emergency procedures specific to multi-trailer rigs.

This test typically has 20 questions, and you must score at least 80 percent to pass. Like the hazmat test, you study from your state's CDL manual. The T test does not require a background check — only the H test does.

Timeline and costs for getting an X endorsement

The hazmat background check is the longest step. After you submit your fingerprints and process, the TSA review typically takes two to four weeks, though it can take longer during high-volume periods. You cannot take the hazmat test until the background check clears.

Once your background check is approved, you can take both the H and T tests on the same day or on different days — your state's DMV will let you schedule them. Each test takes about 20 to 30 minutes. After you pass both, the DMV will issue you a new CDL with the X endorsement, usually within one to two weeks.

Total cost varies by state. The TSA background check fee is typically $85 to $100. Each knowledge test may cost $10 to $20 depending on your state. Some states charge a fee to add the endorsement to your license. Budget $120 to $150 total, though your state's DMV website will show the exact fees.

When you need to renew your X endorsement

The hazmat portion of your X endorsement must be renewed every three years from the date it was issued. You will need to pass the hazmat test again and complete another TSA background check. The doubles/triples portion renews with your regular CDL — typically every four or eight years depending on your state and age.

This means your X endorsement may expire before your CDL itself expires. If your hazmat expires in three years but your CDL expires in five years, you will need to renew hazmat before your full license renewal. Check your CDL to see the expiration dates for each endorsement.

Who typically needs an X endorsement

Drivers who haul fuel, chemicals, explosives, or other hazardous materials need the H portion. Drivers who pull double or triple trailers need the T portion. Many long-haul and regional trucking jobs require the X because they involve both hazmat loads and multi-trailer configurations.

Some specialized roles need only H or only T. A hazmat tanker driver might have H but not T if they pull only single trailers. A driver hauling non-hazmat freight with doubles might have T but not H. Your employer will tell you which endorsements the job requires.

Frequently Asked Questions

Can I get an X endorsement if I have a criminal record?

A criminal record does not automatically disqualify you, but certain convictions will. The TSA background check looks for felonies, drug convictions, and crimes involving explosives or hazmat. If you have a conviction, contact your state's DMV or the TSA to learn whether you are may be able to access before paying for the background check.

Do I have to take the hazmat test in person?

Yes. Your state's DMV administers the hazmat test at a testing facility, usually at a DMV office or an approved third-party testing location. You cannot take it online. The same applies to the doubles/triples test.

What happens if I fail the hazmat or doubles/triples test?

You can retake the test. Most states let you retake it the same day or within a few days. You will pay the test fee again. There is no limit to how many times you can retake it, though some states may require a waiting period between attempts.

If I move to a different state, do I keep my X endorsement?

Your X endorsement transfers to your new state's CDL when you get a license there. You do not need to retake the tests. However, your new state may have different renewal timelines or requirements, so check with your new state's DMV.

Can I drive hazmat or doubles without an X endorsement?

No. Driving hazmat cargo without an H endorsement or pulling doubles/triples without a T endorsement is illegal and can result in fines, license suspension, and criminal charges. Your employer is also liable if they knowingly allow it.