What Are the Texas CDL Endorsement Codes?
An endorsement is a letter added to your CDL that authorizes a specific vehicle type or cargo. Texas DPS uses six:
H — Hazardous Material • N — Tank Vehicle • X — Hazardous Material + Tank Vehicle • T — Double / Triple Trailer • P — Passenger • S — School Bus
Each has its own testing requirement, and some have federal training or background-check steps before you can take the state test. The table below shows what applies to each one.
Texas CDL Endorsement Codes at a Glance
Definitions follow current Texas DPS endorsement and restriction listings. “Available on” matters more than people expect: three of the six can sit on a commercial learner permit, and three cannot.
| Code | Endorsement | Available On | Knowledge Test | Skills Test | ELDT for First-Time Endorsement | Other Requirement / Typical Use |
|---|---|---|---|---|---|---|
| H | Hazardous Material | CDL only | Yes | No separate H skills test | Theory ELDT before the H knowledge test | TSA Security Threat Assessment; placarded hazardous loads |
| N | Tank Vehicle | CDL or CLP | Yes | No separate N skills test | None specific to N | Qualifying tank vehicles |
| X | Hazardous Material + Tank Vehicle | CDL only | H and N knowledge requirements | No separate standalone X skills test | The H requirement applies where the driver is subject to first-time H ELDT | TSA requirement comes via H; hazardous liquids and gases in tanks |
| T | Double / Triple Trailer | CDL only | Yes | No separate T skills test | None specific to T | Applicable Class A combinations |
| P | Passenger | CDL or CLP | Yes | Yes | Theory and behind-the-wheel ELDT before the P skills test | Appropriate passenger vehicle for testing |
| S | School Bus | CDL or CLP | Yes | Yes | Theory and behind-the-wheel ELDT before the S skills test | P also required; Texas school-bus requirements may also apply |
People searching “TX endorsement” usually mean a Texas CDL endorsement. There is no TX code. T is Doubles / Triples. And K — which does appear on Texas licenses — means intrastate only. K is a restriction, not an endorsement: it limits where you may drive rather than authorizing anything extra.
Texas CDL and CLP knowledge examinations have been administered in English only since June 1, 2026. That applies to endorsement knowledge tests as part of the same testing process. See the DPS announcement, Changes to CDL Knowledge Testing, and the DPS CDL application page.
Which Endorsement Do I Need?
Start from the job, not from the code. What the vehicle is and what it carries decide which endorsement applies — there is no endorsement every driver should get.
- Hazardous materials in a tank — X, which carries the H requirements including the TSA assessment
- Non-hazardous tank vehicle — N
- Placarded hazardous loads, not in a tank — H
- Double or triple trailer combinations — T, where the route requires them
- Transit, charter, or shuttle passenger work — P
- School bus — P plus S, plus applicable Texas school-bus requirements
Confirm the exact vehicle, cargo, route, and employer requirement before planning around any endorsement. If you have not got your base CDL yet, start with Texas CDL requirements.
H — Hazardous Material Endorsement
The H endorsement authorizes transporting hazardous materials in quantities that require placarding under federal rules.
ELDT comes first. For a first-time H applicant subject to the rule, the hazardous materials ELDT theory instruction must be completed through a provider listed on the FMCSA Training Provider Registry before taking the state H knowledge test. This is the opposite of P and S, where the training comes before the skills test. Drivers who already held the endorsement before the rule took effect, and applicants covered by an applicable exception, are not swept back in — see FMCSA's ELDT page.
Then the state test and the TSA assessment. You take the H knowledge test at Texas DPS, and separately complete the TSA Security Threat Assessment — a fingerprint-based federal background check. TSA states you must submit new fingerprints at the time of renewal, and that you generally renew the endorsement every five years, though some states may require more frequent review based on shorter licence cycles. TSA does not publish a guaranteed processing time, so treat any figure you hear from a school or recruiter as an estimate, and start early rather than assuming a date.
Disqualifying offences are TSA's list, not ours. Whether a particular record affects your assessment is decided by TSA against its own published criteria. Read them at TSA's HAZMAT Endorsement program rather than working from a summary. For the Texas process end to end, see our Texas Hazmat endorsement guide.
N — Tank Vehicle Endorsement
N authorizes operating a tank vehicle. The federal definition turns on capacity rather than on what the tank looks like: FMCSA guidance describes tanks with an individual rated capacity of more than 119 gallons and an aggregate rated capacity of 1,000 gallons or more, permanently or temporarily attached to the vehicle or chassis. The full definition in 49 CFR 383.5 carries conditions and exclusions that matter in edge cases — portable totes and empty containers among them — so check it against the exact equipment rather than a rule of thumb.
Testing: N requires the applicable knowledge test. There is no separate skills test for the endorsement itself. The knowledge test covers liquid surge and how a partly filled tank changes braking and handling.
N can also be added to a commercial learner permit, unlike H, T, or X.
For the full Texas Tanker process, tank-vehicle definition, testing requirements, and preparation, see our Texas Tanker Endorsement guide.
X — Hazardous Materials + Tank Vehicle Endorsement
X is the combined endorsement for drivers who satisfy the applicable Hazardous Material and Tank Vehicle requirements. It is not a separate course and not a separate standalone skills test — it reflects both underlying qualifications on one code.
What that means in practice: the H side brings the knowledge test and the TSA Security Threat Assessment, and, for a first-time H applicant subject to the rule, the hazardous materials ELDT theory that must be completed before the H knowledge test. The N side brings its own knowledge test. Ask DPS how the codes will be issued on your specific licence transaction rather than assuming any particular automatic behaviour.
What it is for: hauling hazardous liquids and gases in tank vehicles — fuel, industrial chemicals, and compressed gases move this way. Whether a given job needs X, or only N, or only H, depends on the cargo and the equipment.
T — Doubles & Triples Endorsement
T authorizes towing qualifying double or triple trailer combinations. It applies to Class A combination work and cannot be added to a commercial learner permit.
Testing: the applicable knowledge test, covering the handling characteristics of longer combinations — off-tracking, rearward amplification, coupling and uncoupling multiple trailers, and the backing limitations that come with them. There is no separate skills test for the endorsement, and no endorsement-specific federal ELDT requirement.
When it applies: not every carrier runs doubles or triples. It matters where the route or the operation actually uses them — LTL linehaul is the common case. Whether it belongs on your licence is a question about the job you are targeting, not about how easy the test is.
P — Passenger Endorsement
P authorizes operating a vehicle transporting passengers — transit buses, charter and tour coaches, and shuttles are the usual cases. Whether a specific vehicle requires it depends on its design and use, so confirm with Texas DPS for your situation. P is also a prerequisite for the School Bus endorsement.
Testing: a knowledge test plus a skills test conducted in an appropriate passenger vehicle. This is where P differs from N and T — you need access to the right vehicle to be tested in. Confirm who provides the required test vehicle before you enrol anywhere or book a test; not every school or employer supplies one.
ELDT: a first-time P applicant subject to the rule completes both theory and behind-the-wheel training through a provider listed on the FMCSA Training Provider Registry before the state P skills test.
P can be added to a commercial learner permit as well as a CDL.
S — School Bus Endorsement
S authorizes operating a school bus. It requires the Passenger endorsement as a prerequisite, plus its own knowledge and skills testing in an appropriate vehicle. A first-time S applicant subject to the rule completes theory and behind-the-wheel ELDT through a registered provider before the state S skills test.
Texas adds a separate step, and it is not run by the education agency. The School Bus Driver Certification and Re-certification Course is overseen by the DPS School Bus Transportation Program. That state certification is a different thing from the S endorsement tests and from ELDT — passing one does not satisfy the others.
Employers add their own conditions. Districts and contractors commonly layer on background, medical, and training requirements beyond the licence itself. Confirm the full list with the specific employer before planning a timeline.
Which Endorsements Make Sense for Your CDL Job?
Endorsements follow the work. Here is how the common Texas job types line up.
| Job / Vehicle Type | Common Endorsement Need |
|---|---|
| General tractor-trailer freight | No universal endorsement requirement beyond what the specific job needs |
| Fuel or hazardous chemical tanker | X, where applicable |
| Non-hazmat tank vehicle | N |
| LTL doubles / triples | T, where required |
| Transit or charter passenger vehicle | P |
| School bus | P + S, plus applicable Texas school-bus requirements |
These are common examples, not a substitute for confirming the exact vehicle, cargo, route, and employer requirements.
Some specialized jobs may pay differently depending on employer, route, experience, location, schedule, cargo, and working conditions. For pay ranges by position type, see our Texas truck driver salary guide.
When to add an endorsement depends on the job you are targeting. Some can be added later, while first-time H, P, and S applicants may have ELDT requirements before the applicable state test. Check the job requirement first, then plan the endorsement process around it. If you are still choosing a school, see CDL training programs near you in Texas.
Frequently Asked Questions
A CDL endorsement is a letter code added to your commercial driver license that authorizes a specific vehicle type or cargo. Texas uses six: H (hazardous material), N (tank vehicle), X (hazardous material and tank vehicle combined), T (double or triple trailer), P (passenger) and S (school bus). Each has its own testing requirement, and some carry federal training or background-check steps before the state test. An endorsement adds authority; a restriction such as K (intrastate only) takes it away.
There is no universal highest-paying endorsement. Specialized Hazmat, tanker, passenger, and other work may pay differently depending on employer, route, experience, location, schedule, cargo, and working conditions. Choose endorsements based on the job you want, then compare compensation using the Texas truck driver salary guide.
It depends on your situation, and the sequence matters more than the calendar. A first-time H applicant subject to the ELDT rule must complete hazardous materials theory training through a provider listed on the FMCSA Training Provider Registry before taking the state H knowledge test. Separately, you complete the TSA Security Threat Assessment, a fingerprint-based background check. TSA does not publish a guaranteed processing time, so start early rather than planning around a promised date. See our Texas Hazmat endorsement guide.
No endorsement is inherently required just to hold a base Class A or Class B CDL. Endorsements are needed where the vehicle, the cargo, or the job requires them — a tank vehicle, placarded hazardous materials, double or triple trailers, passengers, or a school bus. Which ones you need, and when, follow from the work you are targeting rather than from a standard order.
Eligibility is decided by TSA under its own published criteria, not by Texas DPS or by a school. The Security Threat Assessment is evaluated independently of your CDL application, and some offences affect it while others do not. Rather than working from a summary, read the current criteria on TSA’s HAZMAT Endorsement page and check your own record against them.
X is the combined endorsement for drivers who satisfy both the Hazardous Material and Tank Vehicle requirements — Texas DPS defines it as authorizing the operation of a combination of hazardous material and tank vehicle. It applies to hauling hazardous liquids and gases in tank vehicles. The H side brings the knowledge test, the TSA Security Threat Assessment, and first-time H ELDT theory where applicable; the N side brings its own knowledge test. Ask DPS how the codes will be issued on your specific licence transaction.
No. N requires the applicable knowledge test, and there is no separate skills test for the endorsement itself. The knowledge test covers liquid surge and how a partly filled tank changes braking and handling. For the full Texas process and the tank-vehicle definition, see our Texas Tanker Endorsement guide.
Costs depend on the licence transaction rather than being a per-endorsement charge. Texas DPS publishes current CDL and CLP transaction fees — check the DPS fee schedule for the transaction that applies to you. Hazmat also carries a separate TSA Security Threat Assessment fee, paid to TSA. Check the current DPS and TSA schedules before applying. Skills-test endorsements such as P and S may also involve training or vehicle costs, so confirm who provides the test vehicle.