Tanker endorsement

Which vehicle needs N

N is the tank-vehicle endorsement. 49 CFR 383.5 defines a tank vehicle as any commercial motor vehicle designed to transport any liquid or gaseous materials in a tank or tanks that have an individual rated capacity of more than 119 gallons and an aggregate rated capacity of 1,000 gallons or more. The tank can be permanently or temporarily attached to the vehicle or the chassis.

Checked October 29, 2026: 49 CFR 383.5.

The same definition excludes one case: a commercial motor vehicle transporting an empty storage container tank, not designed for transportation, with a rated capacity of 1,000 gallons or more, temporarily attached to a flatbed trailer. That vehicle is not a tank vehicle. A tank that fails any part of that exception is outside the exclusion. This page does not estimate whether a particular trailer meets the ratings. Read the tank’s rated capacity.

The license class is a separate question. A tank combination can be Class A or another group depending on the weight ratings. The endorsement does not change the class, and the class does not include N. Compare the vehicle in Class A vs Class B if you are still choosing the underlying CDL.

N, H, and X are not the same privilege

49 CFR 383.153 prints N for tank vehicle, H for hazardous materials, and X for a combination of the tank-vehicle and hazardous-materials endorsements. You need N when the vehicle meets the tank definition. You need H when the cargo meets the hazardous-materials definition in 49 CFR 383.5: material that must be placarded under subpart F of 49 CFR part 172, or any quantity of a listed select agent or toxin. When both apply, the CDL shows X rather than treating X as a third, lighter test.

A tank load that is not hazardous material under 49 CFR 383.5 can still require N. Do not add H only because the trailer is a tank. Do not skip N because you already plan to get H. The hazmat endorsement guide covers the H knowledge test, the theory curriculum, and the TSA fee.

One letter is easy to misread on a learner’s permit. Restriction code X there means “No cargo in CMV tank vehicle.” Endorsement code X on a CDL means tank plus hazardous materials. They are both in 49 CFR 383.153, and they are not interchangeable.

The tanker test is a knowledge test

49 CFR 383.93(c)(3) requires a knowledge test for the tank-vehicle endorsement. It does not require a skills test. Passenger and school-bus endorsements are the ones that add a skills test. 49 CFR 383.135(a)(1) sets the passing score for each knowledge test at 80 percent of the questions. The state writes the exam and sets the fee. No state knowledge-test fee was collected for this page.

49 CFR 383.119 says each applicant must know:

• Causes, prevention, and effects of cargo surge on handling.
• Braking when the vehicle is empty, full, and partially full.
• Baffled or compartmented tanks compared with non-baffled vehicles.
• Differences in tank type and construction.
• Cargo surge for liquids of different product densities.
• Road grade and curvature with filled, half-filled, and empty tanks.
• Proper use of emergency systems.
• For drivers of DOT specification tank vehicles, retest and marking requirements.
• Other operating practices that the section does not list by name.

Those are the topics the test must cover. They are not a claim that any one practice quiz is the state exam. Use the tanker practice set to review surge, baffles, and load effects, then study the manual your state gives you.

A permit with N does not authorize a loaded tank

49 CFR 383.93(a)(2) allows a tank-vehicle endorsement on a commercial learner’s permit. Hazardous materials is not on that permit list. 49 CFR 383.153(b)(2)(viii)(C) then limits the permit: a CLP holder with N may only operate an empty tank vehicle, and may not operate any tank vehicle that previously contained hazardous materials and has not been purged of residue.

The permit also carries restriction X, “No cargo in CMV tank vehicle,” when that restriction applies. Practice with an empty, purged tank under the required supervision is not permission to haul the product. The CDL is the document that can carry a loaded-tank endorsement after you pass the knowledge test.

Federal entry-level training names H, not N

49 CFR 380.609(b) requires Training Provider Registry instruction for a first passenger, school bus, or hazardous materials endorsement. The tank-vehicle endorsement is not in that sentence. A first N, by itself, is not given an entry-level curriculum in the sections checked on October 29, 2026. If the tank cargo is hazardous material, the first H path still applies, including the theory curriculum and the TSA threat assessment. Those requirements are on the hazmat endorsement guide, not a tanker tuition figure. What H theory can cover online is in the ELDT online-theory section.

No national tanker-course price or hour count appears in 49 CFR 383.119 or 383.93. A school may still sell tank instruction. Ask which endorsement it covers, whether the vehicle is empty, and what the state test fee is. A directory listing is not a statement that the school offers tank training.