What is the X endorsement on a CDL?

The X endorsement is the combination of the H (hazmat) and N (tanker) endorsements. When you hold both endorsements, your state DMV automatically combines them into a single X designation on your CDL. It authorizes you to transport hazardous materials in tank vehicles, such as fuel tankers.

Can I get the X endorsement without the tanker test?

No. The X endorsement requires passing both the hazmat knowledge test and the tanker knowledge test, plus completing the TSA background check and ELDT training for both endorsements. There is no shortcut to skip either test.

Which endorsement pays the most?

The X endorsement (combined hazmat + tanker) typically pays the most, with premiums of 15-25% over base pay. Fuel hauling, which requires the X endorsement, is one of the highest-paying segments in trucking. The hazmat-only endorsement (H) comes second at 10-20% premium, and tanker-only (N) adds 5-15%.

Do I need a tanker endorsement to haul milk?

Yes. Any liquid transported in a tank with individual capacity over 119 gallons and aggregate capacity over 1,000 gallons requires the N endorsement. Milk tankers exceed these thresholds. However, milk is not hazardous material, so you only need the N endorsement — not the H or X.

How long does it take to get the X endorsement?

The tanker portion (N) can be completed in a day — just ELDT training and a DMV test. The hazmat portion (H) takes 30-60 days due to the TSA background check. Total timeline is typically 4-8 weeks from start to finish if you begin both processes simultaneously.

Do you need a hazmat endorsement to haul fuel?

Yes. Hauling gasoline, diesel, propane, or other fuels in a tank requires the X endorsement, which combines the H (hazmat) and N (tanker) endorsements. Because the cargo is both hazardous and carried in a tank vehicle, the tanker endorsement alone is not enough — you also need the hazmat endorsement and its TSA background check.

Does the tanker (N) endorsement require a background check?

No. The N (tanker) endorsement does not require a TSA security threat assessment, fingerprinting, or background check. You only need to complete ELDT tanker training and pass the tanker knowledge test at your state DMV. The TSA background check applies only to the hazmat (H) endorsement, and therefore to the combined X endorsement.

Hazmat vs Tanker vs X Endorsement

H Endorsement (Hazmat)

The H endorsement authorizes you to transport hazardous materials requiring placards. It is required for any commercial motor vehicle carrying placarded quantities of hazardous materials as defined by 49 CFR Part 383.

Requirements include a TSA security threat assessment, ELDT hazmat training (since February 2022), and passing a written hazmat knowledge test at your state DMV.

N Endorsement (Tanker)

The N endorsement authorizes you to operate a tank vehicle — any commercial motor vehicle designed to transport liquid or gaseous materials within a tank that is permanently or temporarily attached, and has an individual rated capacity of more than 119 gallons and an aggregate capacity of 1,000 gallons or more.

Unlike the H endorsement, the N endorsement does NOT require a TSA background check. It requires only passing a tanker knowledge test at your state DMV and ELDT training.

X Endorsement (Combined)

The X endorsement is simply the combination of H + N. When you hold both the hazmat and tanker endorsements, your CDL shows "X" instead of listing H and N separately. The X endorsement is required for hauling hazardous liquids or gases in tank vehicles — the most common example being fuel hauling.

Important

You cannot apply directly for an X endorsement. You must obtain both the H and N endorsements separately. Your state DMV automatically combines them into X on your CDL.

Is the Combined X Endorsement Worth It?

Pros

+Unlocks the highest-paying tank freight — fuel, propane, and liquid chemical hauling.
+Carries the largest pay premium of any endorsement combination (typically 15-25% over base pay).
+Maximizes the loads you qualify for, since it also covers all H-only and N-only freight.
+The N portion is cheap and fast to add if you already hold H.

Cons

−Requires the TSA security threat assessment, fingerprinting, and the highest total cost of the three options.
−Longest timeline — the hazmat background check can take 30-60 days.
−You must pass and maintain two separate knowledge tests, both renewing with your CDL.
−Overkill if your lanes only involve non-hazardous liquids (N alone) or dry hazmat (H alone).

Requirements Comparison

Requirement	H (Hazmat)	N (Tanker)	X (Both)
TSA Background Check	Required	Not Required	Required
Written Knowledge Test	Hazmat test	Tanker test	Both tests
ELDT Training	Yes	Yes	Both courses
Fingerprinting	Yes	No	Yes
Renewal Cycle	Every 5 years with CDL	Every 5 years with CDL	Every 5 years with CDL
Processing Time	30-60 days (TSA)	Same day (test only)	30-60 days (TSA)

Cost Comparison

Cost Component	H (Hazmat)	N (Tanker)	X (Both)
TSA Fee	$86.50	$0	$86.50
State DMV Fee	$10-$50	$10-$50	$20-$100
ELDT Training	$50-$200	$50-$150	$100-$350
Total Estimate	$146-$336	$60-$200	$206-$536

Pro Tip

The N endorsement is the cheapest CDL upgrade — no TSA fee, no fingerprinting, just a DMV test and ELDT training. If you are looking for a quick, affordable pay boost, start with the tanker endorsement.

Which Freight Requires Which

H Only (Hazmat)

• Dry van hazmat (batteries, paint)
• Flatbed hazmat (compressed gas cylinders)
• Explosives (dry cargo)
• Radioactive materials (dry cargo)

N Only (Tanker)

• Milk and dairy hauling
• Water hauling
• Non-hazardous liquid chemicals
• Food-grade liquid transport

X Required (Both)

• Fuel hauling (gasoline, diesel)
• Liquid chemical hazmat
• Propane and LPG
• Crude oil transport

Pay Premium by Endorsement

Each endorsement adds earning potential. Based on industry data, the typical pay premiums are:

N endorsement (tanker): 5-15% pay premium. Tanker drivers earn $5,000-$15,000 more per year.
H endorsement (hazmat): 10-20% pay premium. Access to higher-paying hazmat freight across all trailer types.
X endorsement (both): 15-25% pay premium. Fuel hauling and liquid hazmat are among the highest-paying trucking segments.

How to Upgrade Endorsements

If you already have one endorsement, adding the other is straightforward:

→Have N, want X: Apply for TSA background check, complete hazmat ELDT, pass hazmat knowledge test. Your N + H automatically becomes X.
→Have H, want X: Complete tanker ELDT, pass tanker knowledge test. No additional background check needed. Your H + N becomes X.

Learn the full process: Hazmat Endorsement Guide | Tanker Endorsement Guide

Common Mistakes to Avoid

Assuming the tanker (N) endorsement alone lets you haul fuel — liquid hazmat in a tank always requires the combined X.
Starting the TSA hazmat background check late — it can take 30-60 days, so begin it first if you want X quickly.
Letting your hazmat endorsement lapse — it renews with your CDL and requires a fresh TSA assessment each cycle, not just a DMV fee.
Skipping ELDT training — hazmat and tanker each require a separate ELDT course from a registered provider before you can take the knowledge test.

How Our Team Maximizes Your Endorsement Value

Endorsement-Matched Loads

We match your endorsements with the highest-paying freight available, ensuring you get the premium rates your credentials deserve.

Credential Planning

We advise carriers on which endorsements to pursue based on their operating lanes and earning goals.

Frequently Asked Questions

Ahmad Qazi

Founder & CEO, O Trucking LLC

Published: February 19, 2026Updated: June 30, 2026

5+ Years Experience80+ Carriers ServedIndustry Data Verified

Sources:

FMCSA CDL Requirements 49 CFR Part 383

Written by Ahmad Qazi, founder of O Trucking LLC, drawing on 9+ years dispatching for owner-operators. Learn more about us.

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Hazmat vs Tanker vs X Endorsement: Which Do You Need?

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