CDL Restriction Codes Explained: Complete Guide to Every Restriction (2026)
By Penn Mahana | Published 2026-08-05
Look at your CDL and you'll see letters in the "Restrictions" field. Each one limits what you can drive — and each one affects your job options.
Disclaimer: This guide is for educational purposes only. CDL requirements, fees, and regulations are set by the FMCSA and individual state DMVs. Always verify current requirements with your state DMV and consult official FMCSA resources for the most up-to-date information.
Some restrictions are easy to remove. Others require retesting. A few are permanent. This guide covers every CDL restriction code: what it means, how it limits you, and how to get it removed.
Quick Reference Table
| Code | Name | What It Means | Removable? |
|---|---|---|---|
| L | No Air Brake Equipped CMV | Can't drive vehicles with air brakes | Yes — pass Air Brakes test |
| Z | Air Over Hydraulic Brakes Only | Limited to air-over-hydraulic systems | Yes — pass full Air Brakes test |
| E | No Manual Transmission | Automatic transmission only | Yes — retest in manual |
| M | No Class A Passenger Vehicle | Can't drive Class A buses | Yes — retest in Class A bus |
| N | No Class A and B Passenger Vehicle | Can't drive Class A or B buses | Yes — retest in Class B bus |
| O | No Tractor-Trailer | Can't drive tractor-trailer combinations | Yes — retest in tractor-trailer |
| K | Intrastate Only | Can't cross state lines | Yes — update medical cert |
| V | Medical Variance | Medical exemption on file | Depends on condition |
| W | Farm Vehicle Only | Limited to farm-related driving | Yes — retest for full CDL |
| P | No Passengers in CMV Bus | Can't drive passenger buses | Yes — pass Passenger test |
| X | No Cargo in CMV Tank Vehicle | Can't haul cargo in tank vehicles | Yes — pass Tanker test |
| T | 60-Day Temporary License | Temporary CDL, 60-day limit | Expires automatically |
What Are CDL Restrictions?
CDL restrictions are limitations placed on your commercial driver's license that define what you cannot drive. They appear as single-letter codes on the front of your license, typically in the "Restrictions" or "Endorsements/Restrictions" field.
Restrictions exist for two main reasons:
Limited Testing
If you took your CDL skills test in a truck without air brakes (L restriction) or in an automatic (E restriction), the restriction reflects what you demonstrated competence in.
Medical or Legal Limits
The K restriction (Intrastate Only) is based on medical self-certification. The V restriction indicates a medical variance or exemption.
Employability Warning: Restrictions are not punishments, but they do limit your job options. A driver with an E restriction cannot take a job requiring a manual transmission.
Complete List of CDL Restriction Codes
L Restriction — No Air Brake Equipped CMV
What it means:
You cannot operate any commercial motor vehicle equipped with air brakes.
Practical impact:
Very limiting. Most Class A tractor-trailers use air brakes. You're limited to smaller vehicles with hydraulic brakes.
How to remove it:
- Study the Air Brakes section of the CDL Manual
- Pass the Air Brakes knowledge test
- Retake the CDL skills test in a vehicle with air brakes
Z Restriction — Air Over Hydraulic Brakes Only
What it means:
You can operate vehicles with air-over-hydraulic brake systems, but not full air brake systems.
Practical impact:
Common in medium-duty trucks. You cannot drive standard tractor-trailers with full air brake systems.
How to remove it:
Pass the full Air Brakes knowledge test and retake the skills test in a vehicle with full air brakes.
E Restriction — No Manual Transmission
What it means:
You can only drive commercial vehicles with automatic transmissions.
Practical impact:
Less limiting than before due to AMTs, but still reduces options with smaller carriers and specialty hauling.
How to remove it:
Practice driving a manual-transmission CMV and retake the CDL skills test in a manual-transmission vehicle.
M & N Restrictions — Passenger Vehicles
M Restriction:
Cannot operate Class A passenger vehicles. Remove by retaking the skills test in a Class A passenger vehicle.
N Restriction:
Cannot operate Class A or B passenger vehicles. Remove by upgrading to a Class B or A CDL and retaking the skills test.
O Restriction — No Tractor-Trailer
What it means:
You cannot operate tractor-trailer combinations.
Practical impact:
Limits access to most common Class A trucking jobs.
How to remove it:
Retake the CDL skills test in a tractor-trailer (fifth-wheel) combination.
K Restriction — Intrastate Only
What it means:
You can only operate CMVs within the state that issued your CDL. You cannot cross state lines.
Practical impact:
Significant limitation for long-haul and regional drivers. Common for drivers under 21.
How to remove it:
- Meet age requirement (21 for interstate)
- Obtain valid DOT medical certificate
- Update self-certification to "interstate" with your DMV
V Restriction — Medical Variance
What it means:
You have a medical variance or exemption on file with the FMCSA.
Practical impact:
Signals that you have a condition that would normally disqualify you, but you've been granted an exemption.
Crucial: You must carry your medical variance documentation while driving. Failure to produce it during an inspection can result in an out-of-service order.
W Restriction — Farm Vehicle Only
What it means:
You can only operate CMVs for farm-related purposes within 150 miles of the farm.
Practical impact:
Restricted to agricultural operations. Cannot be used for general commercial driving.
How to remove it:
Complete full CDL training and pass all required knowledge and skills tests for the class you need.
P & X Restrictions — Passenger & Tanker Cargo
P Restriction (No Passengers):
You have the Passenger endorsement but didn't demonstrate loading/unloading. Remove by retaking the skills test demonstrating these procedures.
X Restriction (No Cargo in Tank):
You have the Tanker endorsement but didn't demonstrate cargo handling. Remove by retaking the skills test demonstrating proper cargo handling.
T Restriction — 60-Day Temporary License
This is a temporary CDL issued while your permanent license is being processed. You can drive normally during this 60-day period.
How to remove it:
This expires automatically when you receive your permanent CDL.
How to Remove a CDL Restriction
Identify the restriction
Check your CDL and understand what is required for removal.
Study and prepare
Read the CDL Manual and take practice tests.
Pass the knowledge test
Required for restrictions like L and Z.
Schedule a skills test
Must be in a vehicle that does NOT have the restriction.
Pass the skills test
Demonstrate competence in the non-restricted vehicle.
Pay the license update fee
DMV will issue your updated CDL.
CDL Restrictions vs. Endorsements
| Feature | Restrictions | Endorsements |
|---|---|---|
| What they do | Limit what you CAN'T drive | Expand what you CAN drive |
| Appearance | Single letters in Restrictions field | Single letters in Endorsements field |
| How you get them | Testing in limited vehicle, or medical/legal limits | Passing additional knowledge and skills tests |
| Goal | Remove them (usually) | Add them (as your career grows) |
How Restrictions Affect CDL Jobs
Minimal Impact
V restriction (medical variance) or M restriction (Class A passenger jobs are rare).
Moderate Impact
E restriction (automatic only), K restriction (intrastate only), or Z restriction.
Severe Impact
L restriction (no air brakes), O restriction (no tractor-trailer), or W restriction (farm only).
Tip for Job Hunters: Be upfront about restrictions. Prioritize removing the L restriction — it's the most limiting and the most removable.
Frequently Asked Questions
Can I get a CDL without air brakes?
Yes, but you'll have an L restriction. You can only drive vehicles with hydraulic brakes. This significantly limits your job options — most Class A tractor-trailers use air brakes.
How do I know what restrictions are on my CDL?
Look at the front of your CDL in the "Restrictions" field. It will show one or more single-letter codes. Your state DMV can also provide a complete driving record.
Can I have multiple restrictions?
Yes. It's common to see multiple codes, such as "E, K" (automatic only and intrastate only). Each must be removed separately.
Does the E restriction (automatic only) really matter anymore?
It matters less than before, but still limits you with smaller carriers, owner-operators, and specialty segments like logging or construction.
What's the difference between the L and Z restrictions?
L means no air brakes at all. Z means you can drive air-over-hydraulic systems but not full air brakes. Both exclude standard tractor-trailers.
How long does it take to remove a restriction? la
Knowledge test restrictions (L, Z) can be removed in a day. Skills test restrictions (E, O, M, N, P, X) depend on DMV availability. Medical restrictions (K, V) depend on certification timelines.
Ready to Remove a Restriction?
Start with our free CDL practice tests — including Air Brakes, Combination Vehicles, and every endorsement to ensure you pass your retest first try.
Take a Free CDL Practice Test