What the Tank and Hazmat Endorsement Covers

The Tank endorsement (T) and Hazmat endorsement (H) are two separate CDL endorsements that allow you to haul specific cargo. The Tank endorsement lets you drive a commercial vehicle with a tank permanently attached or mounted that holds liquid or gas — things like milk, fuel, water, or propane. The Hazmat endorsement lets you transport materials the Department of Transportation classifies as hazardous — explosives, flammable liquids, toxic substances, and others.

You do not need both. A driver hauling regular freight in a tanker truck needs only the Tank endorsement. A driver hauling hazardous materials in a regular box truck needs only the Hazmat endorsement. But if you haul hazardous liquids in a tanker — gasoline, diesel, or chemicals — you need both endorsements on your CDL.

Both endorsements require passing a written test beyond your CDL knowledge test. The Hazmat endorsement also requires a federal background check and fingerprinting through the Transportation Security Administration (TSA). Neither endorsement requires behind-the-wheel testing.

Key Takeaways

  • Tank endorsement (T) allows you to drive vehicles with permanently attached tanks carrying liquids or gases; Hazmat endorsement (H) allows you to transport materials classified as hazardous by the Department of Transportation.
  • You need both endorsements only if you haul hazardous materials in a tank vehicle — otherwise you need only one.
  • Both require passing a written knowledge test at your state's DMV; Hazmat also requires TSA background clearance and fingerprinting.
  • Hazmat endorsement processing takes several weeks because of the federal background check, so plan ahead if your job requires it.
  • Some states charge separate fees for each endorsement, and some employers require both even if the job does not technically need both.

Tank Endorsement Requirements and Testing

To add the Tank endorsement to your CDL, you must already hold a valid CDL in your state. You then study the Tank endorsement material — your state's DMV provides a study guide that covers tank vehicle physics, cargo surge, weight distribution, and safe handling of liquid loads. The test is typically 20 questions, and you must score at least 80 percent to pass.

The test focuses on practical knowledge: how liquid sloshes inside a tank during braking, why partially filled tanks are more dangerous than full ones, how to inspect a tank vehicle before driving, and what to do if a tank ruptures or leaks. You take the test at your state's DMV office, the same place you took your CDL written test.

There is no road test for the Tank endorsement. Once you pass the written test, the endorsement is added to your CDL. Some states add it when ready; others mail you an updated license within one to two weeks.

Hazmat Endorsement: TSA Background Check and Fingerprinting

The Hazmat endorsement requires more than a written test. After you pass the Hazmat knowledge test at your DMV, you must submit to a federal background check and fingerprinting through the TSA. This is a security requirement because hazardous materials can pose a public safety risk.

The process works like this: you pass the written test at your DMV, then your state sends your information to the TSA. The TSA runs a background check that includes criminal history, immigration status, and other security factors. You will be fingerprinted — either at a designated location your state provides or at a private fingerprinting service (you may pay a fee for this, usually $10 to $20). The TSA then approves or denies your Hazmat endorsement.

The entire process typically takes two to four weeks, though it can take longer if the TSA needs more information or if there are delays in fingerprinting. During this time, you cannot legally transport hazardous materials, even if you have passed the written test. You must wait for TSA approval and for your state to issue an updated license with the H endorsement.

What Disqualifies You from Hazmat Endorsement

The TSA will deny your Hazmat endorsement if you have certain criminal convictions, immigration violations, or security-related issues. Disqualifying offenses include felonies involving explosives, weapons, or drugs; crimes of violence; human trafficking; and certain immigration violations. A single conviction does not automatically disqualify you — the TSA evaluates the nature of the crime, when it occurred, and your circumstances since then.

You may also be denied if you are not a U.S. citizen or permanent resident, though some states have different rules. If you are denied, the TSA will send you a letter explaining why. You have the right to request reconsideration or appeal, though the process is lengthy and success is not may provide.

If you have a criminal history and are unsure whether you will be approved, contact your state's DMV before paying test fees. Some states allow you to request a preliminary TSA information before you take the written test, which can save you money and time.

Tank and Hazmat Endorsement Costs and Timeline

Costs vary by state. Most states charge between $10 and $50 for each endorsement test. Some states charge an additional fee to add the endorsement to your license — typically $5 to $25. Fingerprinting for Hazmat, if required in your state, usually costs $10 to $20. If you use a private fingerprinting service, the cost may be higher.

The timeline depends on which endorsement you need. Tank endorsement alone usually takes one to two weeks from test to updated license. Hazmat endorsement takes two to four weeks because of the TSA background check. If you need both, you can take both tests on the same day, but your license will not be updated until both approvals come through — so the timeline is determined by whichever takes longer, usually the Hazmat check.

Some employers will let you start driving while your endorsement is pending, as long as you have passed the written test and are waiting for the license to arrive. Others will not. Check with your employer before you schedule your tests.

Renewing and Maintaining Your Endorsements

Tank and Hazmat endorsements renew with your CDL. When your CDL expires, you must renew both the license and any endorsements at the same time. You do not need to retake the Tank test when you renew — most states straightforward renew the endorsement as part of your CDL renewal.

Hazmat endorsement renewal is different. You must retake the Hazmat knowledge test every time your CDL renews. You also must go through TSA background clearance again. The TSA re-checks your background to make sure nothing has changed since your last approval. This process takes the same two to four weeks as the initial approval.

If your Hazmat endorsement is denied during renewal, your CDL will be issued without the H endorsement. You can reapply after addressing whatever issue caused the denial, but you cannot drive hazardous materials in the meantime.

Tank and Hazmat Together: When You Need Both

You need both endorsements if your job requires you to haul hazardous materials in a tank vehicle. Common examples include gasoline tanker drivers, propane delivery drivers, and chemical transport drivers. In these roles, you are subject to both Tank regulations (how to safely handle a tank vehicle) and Hazmat regulations (how to safely handle hazardous cargo).

Some employers require both endorsements even if the job does not technically require both — for example, a company might require all their CDL drivers to have Hazmat endorsement for flexibility in assigning loads. If your job posting says "Tank and Hazmat required," get both before you explore or start the job.

If you already have one endorsement and need to add the other, you can do so at any time. You do not need to wait for your CDL to renew. straightforward go to your state's DMV, pay the test fee, study the material, and take the test. The new endorsement will be added to your existing license.

Frequently Asked Questions

Can I take the Tank and Hazmat tests on the same day?

Yes. Most states allow you to take both tests in one visit to the DMV. You will need to study for both and bring the required documents for each. However, your updated license will not arrive until both approvals are processed, which means you will wait for the Hazmat background check to complete.

What happens if I fail the Tank or Hazmat test?

You can retake the test. Most states let you retake it when ready or within a few days, though some require you to wait a certain number of days between attempts. You will pay the test fee again. There is no limit to how many times you can retake it.

Do I lose my Tank endorsement if I get a DUI or other violation?

A DUI or traffic violation does not automatically remove your Tank endorsement. However, if your CDL is suspended or downgraded, your endorsements go with it. If your Hazmat endorsement is revoked due to a security issue, you lose only the H endorsement — your Tank endorsement and CDL remain valid.

Can I get Hazmat endorsement if I have a felony conviction?

It depends on the type of felony and how long ago it occurred. The TSA evaluates each case individually. Convictions involving explosives, weapons, or violence are more likely to result in denial. Contact your state's DMV to ask about a preliminary TSA information before you pay for the test.

How long does the TSA background check take?

Typically two to four weeks from the time your state submits your information to the TSA. Delays can happen if the TSA needs more information, if fingerprinting is delayed, or if there are issues with your background. Some states process faster than others.