CDL Endorsements Explained: What Hiring Managers Need to Know to Hire Smarter
Aug 4, 2025
4 min
As a hiring manager in the trucking or transportation industry, you know the pressure: fill empty seats, keep trucks moving, and ensure every driver you onboard is fully qualified. One of the most overlooked yet essential pieces of this puzzle? CDL endorsements.
Understanding CDL endorsements is critical to hiring the right drivers for the right jobs and ensuring compliance and operational efficiency from day one.
What Are CDL Endorsements?
A CDL (Commercial Driver’s License) gives a driver permission to operate certain types of commercial vehicles. But a base CDL isn’t enough for many roles.
Endorsements are add-ons that certify drivers to handle specialized vehicles or cargo, like hazardous materials or passenger transport.
Each endorsement requires extra testing and, in some cases, background checks. For hiring managers, that means one thing: you must verify endorsements carefully to ensure your driver is legally qualified for the job.
Key CDL Endorsements to Watch For
When evaluating driver candidates, knowing which CDL endorsements they hold, and which ones your roles require, is critical. Each endorsement allows a driver to operate specialized vehicles or carry specific types of cargo. Below is a breakdown of the most common endorsements hiring managers should be familiar with:
T – Double/Triple Trailers
What it Covers: Authorizes a driver to haul two or three trailers simultaneously. These are typically longer, more complex setups that require increased skill and caution.
When You Need It:
Long-haul freight carriers
LTL (Less Than Truckload) operations
Regional routes with high-volume trailer swaps
Hiring Tip: Ensure drivers with a T endorsement also have a strong safety record and experience with maneuvering multi-trailer configurations. Not all drivers with a CDL-A have experience in this area.
P – Passenger
What it Covers: Permits a driver to operate any commercial vehicle designed to transport 16 or more passengers, including the driver.
When You Need It:
Transit bus services
Employee shuttle operations
Airport or hotel transport services
Hiring Tip: Verify a clean driving history and strong interpersonal skills, as passenger-facing roles involve public interaction. A road test focused on passenger safety procedures is also recommended.
S – School Bus
What it Covers: A specialized passenger endorsement for school buses. It requires both the “P” endorsement and additional testing, including background checks and fingerprinting.
When You Need It:
School district contractors
Charter services for educational institutions
Any K-12 student transport program
Hiring Tip: Confirm that the driver has completed a state and FBI background check and meets your local Department of Education requirements. This endorsement carries some of the strictest safety standards.
N – Tanker Vehicles
What it Covers: Allows drivers to operate tank vehicles designed to transport liquids or gases, either hazardous or non-hazardous.
When You Need It:
Fuel delivery companies
Agricultural chemical haulers
Milk, water, or other bulk liquid carriers
Hiring Tip: Look for drivers with experience handling surge (the movement of liquid inside tanks during transit) and knowledge of specific loading/unloading procedures. Mismanagement of liquid loads can pose serious safety risks.
H – Hazardous Materials (HazMat)
What it Covers: Certifies that a driver is authorized to transport hazardous materials, including flammable, explosive, toxic, or radioactive substances.
When You Need It:
Fuel and propane transport
Industrial chemical distribution
Waste management and remediation
Hiring Tip: Confirm that the driver has passed the required TSA background check, fingerprinting, and HazMat knowledge exam. This endorsement must be renewed every five years, and hiring managers should track expiration dates carefully.
X – Combination of Tanker and HazMat
What it Covers: A combined endorsement that covers both the N (Tanker) and H (HazMat) certifications. It’s a must-have for drivers hauling hazardous liquids, like fuel or chemicals.
When You Need It:
Fuel tanker fleets
Chemical transport operations
Refineries or industrial material suppliers
Hiring Tip: This endorsement is a strong signal of a highly qualified driver. Prioritize applicants with the “X” endorsement when hiring for specialized or high-liability freight. Ensure your onboarding and compliance workflows can verify and document both HazMat and Tanker qualifications.
When it comes to CDL endorsements, the cost of oversight is high. Non-compliance can result in fines, liability, and downtime.
Why Endorsements Matter to You
As a hiring manager, endorsements impact more than just compliance. They directly affect your team’s ability to operate at full capacity.
Avoid Compliance Issues
Hiring a driver without the correct endorsement is not just risky — it’s illegal. That exposes your company to DOT audits, fines, and possible downtime.
Match the Right Driver to the Right Job
Endorsements help you filter applicants based on what they’re actually certified to do, saving you time and avoiding costly mismatches.
Improve Time-to-Hire
When you have visibility into which candidates already have the endorsements you need, you can fast-track interviews and offers, keeping your fleet productive.
How Double Nickel Helps Hiring Managers Hire Smarter
Hiring drivers is already hard and verifying their qualifications shouldn’t be. That’s why Double Nickel is built specifically for hiring managers in transportation.
Double Nickel is an all-in-one platform designed to help you hire qualified drivers faster, stay compliant, and reduce cost-per-hire. All without juggling spreadsheets, emails, and missed connections.
What You Get:
+80% Lead Contact Rate - Instantly connect with applicants via our AI Virtual Recruiter that calls, texts, and emails on your behalf.
20% Lower Cost to Hire - Improve lead-to-application conversion with a mobile-friendly, password-free DoT application experience.
10+ Hours Saved Weekly per Team Member - Automate repetitive tasks like qualification screening and report collection, so you can focus on hiring.
Make CDL Hiring a Strength, Not a Bottleneck
The difference between a fully-staffed, compliant fleet and one stuck in neutral often comes down to your hiring process. CDL endorsements are a crucial part of that, and with Double Nickel, you never have to worry about missing a qualification again.
Book a demo today and see how Double Nickel simplifies driver hiring, improves compliance, and keeps your team efficient and in control.


