49 CFR Part 383: Commercial Driver's License Standards

Part 383 sets the federal minimum standards States must follow when issuing a commercial driver’s license, and the standards drivers and employers must meet to use one. It answers four questions: who needs a CDL, what classes and endorsements cover which vehicles, what conduct disqualifies a driver and for how long, and what drivers and employers must tell each other.

For a carrier, the operative parts are the disqualification tables in 49 CFR 383.51 and the employer prohibitions in 383.37. Everything else is licensing mechanics handled by the State.

Who does 49 CFR Part 383 apply to?

49 CFR 383.3(a): “The rules in this part apply to every person who operates a commercial motor vehicle (CMV) in interstate, foreign, or intrastate commerce, to all employers of such persons, and to all States.”

That intrastate reach is unusual. Most of the FMCSRs stop at the state line unless a State adopts them; Part 383 does not. If you run a 26,001-pound truck entirely inside one state, your driver still needs a CDL.

A commercial motor vehicle for CDL purposes is defined by the vehicle groups in 49 CFR 383.91:

Group	Vehicle	Threshold
A — combination vehicle	Any combination of vehicles	GCWR of 26,001 lbs or more, provided the GVWR of the towed unit(s) exceeds 10,000 lbs
B — heavy straight vehicle	Any single vehicle, or such a vehicle towing a unit of 10,000 lbs GVWR or less	GVWR of 26,001 lbs or more
C — small vehicle	Any vehicle or combination meeting neither Group A nor Group B	Designed to transport 16 or more passengers including the driver, or transporting hazardous materials requiring placards

Section 383.3 also carries the exceptions. States must exempt active duty military personnel, reserves and National Guard on active duty, dual-status military technicians, and Coast Guard personnel operating military vehicles (383.3(c)). States may exempt farmers operating farm vehicles within 150 miles of the farm, firefighters and emergency responders in equipped emergency vehicles, and drivers removing snow and ice (383.3(d)). States may also issue restricted CDLs for isolated Alaska roads (383.3(e)), farm-related service industries such as custom harvesters, agri-chemical businesses, farm retail outlets and livestock feeders (383.3(f)), and pyrotechnic operations (383.3(g)). Drivers of “covered farm vehicles” are exempt outright (383.3(h)).

Two cautions. Most of these are State options, not federal entitlements — check your own State before relying on one. And an exemption from the CDL requirement is not an exemption from driver qualification, medical certification, or hours of service.

What are the CDL classes, endorsements, and restrictions?

Class A, B, and C track the vehicle groups above. On top of the class, 49 CFR 383.93 adds endorsements, each requiring its own knowledge test and, for some, a skills test:

• T — double/triple trailers (knowledge test)
• P — passenger vehicles (knowledge and skills tests)
• S — school bus (knowledge and skills tests)
• N — tank vehicles (knowledge test)
• H — hazardous materials (knowledge test; also requires a TSA security threat assessment)

Restrictions narrow what the license authorizes, based on the vehicle the driver tested in. 49 CFR 383.95 sets them: L if the applicant tested without air brakes (restricted from any CMV with air brakes), E if the applicant tested on an automatic transmission (restricted from a manual), O if the applicant tested in a combination not connected by a fifth wheel (restricted from tractor-trailers), and V to flag a medical variance on the CDLIS record and the license. Further restrictions cover air-over-hydraulic brake systems and passenger applicants who tested in a smaller vehicle group.

The E restriction is the one that quietly costs carriers loads: a driver who trained on an automatic cannot legally take a manual tractor, and a dispatcher who assigns one puts the carrier in violation of 383.37(a).

What is a commercial learner’s permit, and what can a CLP holder do?

49 CFR 383.25 governs the CLP. The holder must be at least 18, hold a valid driver’s license from the issuing jurisdiction, and have passed the required knowledge tests. Three rules matter operationally:

1. Supervision. The CLP holder must at all times be accompanied by the holder of a valid CDL with the proper class and endorsements, physically present in the front seat next to the CLP holder — or, in a passenger vehicle, directly behind the driver — providing direct supervision.
2. The 14-day rule. A CLP holder is not eligible to take the CDL skills test in the first 14 days after initial issuance of the CLP.
3. Validity. The CLP is valid for no more than one year from initial issuance, and may be renewed within that window without retaking the knowledge tests.

Only P, S, and N endorsements may appear on a CLP, each restricted: no passengers other than instructors and examiners on P or S, and tanks must be empty and purged of hazardous material residue for N. All other federal endorsements are prohibited, and a CLP holder may not transport hazardous materials.

Do CDL applicants have to complete entry-level driver training?

Yes, for credentials obtained for the first time on or after February 7, 2022. 49 CFR 383.71 requires an applicant to complete the training prescribed in Part 380 Subpart F before taking the skills test for a Class A or B CDL for the first time, the skills test for a P or S endorsement for the first time, or the knowledge test for an H endorsement for the first time. The same requirement applies when upgrading an existing CDL to Class A or B. The training must be administered by a provider listed on FMCSA’s Training Provider Registry — details on the Part 380 ELDT page.

What are the CDL disqualification periods?

This is the section carriers most need to get right, and the one most often misquoted. 49 CFR 383.51(a) sets the frame: a person required to hold a CLP or CDL who is disqualified must not drive a CMV, and an employer must not knowingly allow, require, permit, or authorize a disqualified driver to drive one. Each conviction arising from a separate incident is counted separately.

Table 1 — major offenses. These are the offenses in 383.51(b): driving a CMV under the influence of alcohol or a controlled substance; driving a CMV with a blood alcohol concentration of 0.04 percent or more; refusing to take a required alcohol test; leaving the scene of an accident; using a vehicle to commit a felony; driving a CMV while the CLP or CDL is revoked, suspended, or canceled, or while disqualified; and causing a fatality through negligent operation of a CMV.

Offense category	1st offense, in a CMV	1st offense, in a non-CMV	1st offense, in a placarded hazmat CMV	2nd offense
Major offenses (383.51 Table 1, items 1–8)	1 year	1 year, where the table applies it	3 years	Life
Using a CMV in a felony involving manufacturing, distributing, or dispensing a controlled substance	Life — not eligible for 10-year reinstatement	Life	Life	Life
Using a CMV in a felony involving a severe form of trafficking in persons	Life — not eligible for 10-year reinstatement	—	Life	Life

Three of the Table 1 offenses — 0.04 BAC, driving on a revoked or suspended CLP/CDL, and causing a fatality by negligent operation — are defined only in terms of operating a CMV, so no non-CMV period applies to them.

A lifetime disqualification is not always permanent. Under 383.51(a), a State may reinstate a driver after 10 years if the driver voluntarily entered and successfully completed an appropriate rehabilitation program. That relief is available once; a subsequent Table 1 conviction bars further reinstatement. The controlled-substance and human trafficking felony disqualifications carry no reinstatement at all.

Table 2 — serious traffic violations. A single conviction does not disqualify. The periods run on repeat convictions from separate incidents within a three-year window.

Violation	2nd conviction in 3 years	3rd or subsequent in 3 years
Excessive speeding — 15 mph or more over the limit	60 days	120 days
Reckless driving	60 days	120 days
Improper or erratic lane changes	60 days	120 days
Following too closely	60 days	120 days
Traffic control violation arising in connection with a fatal accident	60 days	120 days
Driving a CMV without obtaining a CLP or CDL, without one in possession, or without the proper class or endorsement	60 days	120 days
Texting while driving a CMV	60 days	120 days
Using a hand-held mobile telephone while driving a CMV	60 days	120 days

Under 383.51(c), a serious traffic violation committed in a non-CMV counts toward these periods only if the conviction results in the revocation, cancellation, or suspension of the CLP or CDL holder’s license or non-CMV driving privileges.

Table 3 — railroad-highway grade crossing violations. These apply when the driver is operating a CMV, and cover failing to slow down and check that the tracks are clear, failing to stop before reaching the crossing when the tracks are not clear, failing to stop at a crossing where a stop is required, failing to have sufficient space to drive completely through without stopping, disobeying a traffic control device or enforcement officer’s directions, and failing to negotiate a crossing because of insufficient undercarriage clearance.

Grade crossing convictions (separate incidents within 3 years)	Disqualification
1st	At least 60 days
2nd	At least 120 days
3rd or subsequent	At least 1 year

Table 4 — out-of-service order violations. Counted over a 10-year window, and considerably heavier than most carriers expect.

Out-of-service order violation	1st	2nd in 10 years	3rd or more in 10 years
While operating a CMV (general)	180 days to 1 year	2 to 5 years	3 to 5 years
While operating a CMV transporting placarded hazardous materials, or designed to transport 16 or more passengers including the driver	180 days to 2 years	3 to 5 years	3 to 5 years

Separately, since November 18, 2024, State Driver Licensing Agencies must remove commercial driving privileges from any driver in “prohibited” status in the FMCSA Drug and Alcohol Clearinghouse — a downgrade rather than a Part 383 disqualification, with the same practical effect. See Part 382.

What must drivers and employers notify each other about?

Obligation	Citation	Deadline
Driver notifies employer of a conviction for any motor vehicle traffic violation (other than parking), in any vehicle type	49 CFR 383.31	Within 30 days of the conviction, in writing
Driver notifies the State of domicile of an out-of-State conviction	Removed	No longer a federal requirement — see below
Driver notifies employer of a license suspension, revocation, cancellation, loss of CMV driving privilege, or disqualification	49 CFR 383.33	Before the end of the business day following the day the driver received notice
Applicant provides 10 years of previous CMV employment history; employer must request it	49 CFR 383.35	At the time of application

The written notification to the employer under 383.31 must contain the driver’s full name, license number, date of conviction, the offense and any resulting suspension or revocation, whether the violation occurred in a CMV, the location, and the driver’s signature.

Changed on July 22, 2026. FMCSA’s final rule at 91 FR 37047 removed the federal requirement that a CDL holder self-report certain convictions to their State Driver Licensing Agency. The duty to notify your employer is unchanged. Two cautions: your State may still require self-reporting under its own law, and your employment policy may require notification regardless — so confirm your State before you change any internal process. See our regulatory changes tracker.

49 CFR 383.37 places the mirror-image duty on you. You may not knowingly allow, require, permit, or authorize a driver to operate a CMV: without a current CLP or CDL, without the proper class or endorsements, or in violation of a restriction (383.37(a)); during any period the driver is disqualified, has lost the right to operate, or is suspended, revoked, or canceled (383.37(b)); while holding more than one CLP or CDL (383.37(c)); while the driver, the vehicle, or the carrier operation is under an out-of-service order (383.37(d)); or in violation of any Federal, State, or local law on railroad-highway grade crossings (383.37(e)).

What auditors actually check

Part 383 findings surface inside a driver qualification review, so an investigator works from your driver list:

1. A valid CDL of the right class with the right endorsements for every driver, matched against the vehicles they actually operated. Tank, hazmat, doubles, and passenger assignments get checked hardest.
2. Restrictions — the E (automatic transmission) and L (no air brakes) codes against dispatch records.
3. Motor vehicle records. Part 391 requires an MVR at hire and an annual review; the investigator reads them for disqualifying convictions you should have caught.
4. Conviction notifications to the employer under 383.31, cross-referenced against the MVR. A conviction on the MVR with no notification in the file is a finding against the driver and a warning sign about your review process. (The separate State-of-domicile self-report was removed federally on July 22, 2026.)
5. The 10-year employment history required by 383.35 on the application.
6. Drivers who kept driving after a disqualification, downgrade, or Clearinghouse prohibition — the acute violation of 383.37(b), and the one that most often escalates an investigation.
7. Out-of-service order violations in roadside history.

Steps 3, 4, and 6 are one question asked three ways: did you know your driver’s license status, and when. Carriers that run continuous MVR monitoring and keep expirations, endorsements, and medical cards on one driver compliance record answer it in seconds. The DOT audit preparation walkthrough covers assembling the file; the audit readiness quiz tests it.

Most common Part 383 violations

• Driving without the proper CDL class or endorsement. Most often a tank or hazmat load moved on a license without N or H.
• Allowing a disqualified or suspended driver to operate (383.37(b)). Treated as acute, and easy to prove from the MVR date.
• Driving a CMV while the CDL is suspended, revoked, or canceled. A Table 1 major offense in its own right — one year first, life second.
• Violating a restriction. Assigning a manual transmission to a driver with an E restriction, or an air-brake vehicle to a driver with an L restriction.
• Failure to notify the employer of a conviction within 30 days (383.31).
• CLP violations. The supervising CDL holder not in the front seat, or a skills test attempted inside the 14-day window.
• Operating in violation of an out-of-service order. The heaviest disqualification schedule in the part, starting at 180 days.
• More than one driver’s license (383.21). Rare now that CDLIS is universal, but still cited.

Civil penalties attach to many of these, for both driver and employer. The dollar figures are set out in Part 386 and adjusted for inflation annually, so check FMCSA’s current penalty schedule rather than any figure quoted in an article — including this one.

Frequently asked questions

How long is a driver disqualified for a first DUI in a commercial vehicle? One year (49 CFR 383.51, Table 1). Three years if the offense occurred while operating a CMV required to be placarded for hazardous materials. A second major offense is a lifetime disqualification.

What is a lifetime CDL disqualification? A second conviction for any combination of the Table 1 major offenses, from separate incidents. A State may reinstate after 10 years if the driver voluntarily completed an appropriate rehabilitation program — once only. Felony controlled-substance manufacturing or distribution, and felony human trafficking, involving a CMV carry a lifetime disqualification with no reinstatement.

What counts as a serious traffic violation? Speeding 15 mph or more over the limit, reckless driving, improper or erratic lane changes, following too closely, a traffic control violation in a fatal accident, driving without the proper CLP/CDL class or endorsement, texting, and hand-held phone use. Two in three years is 60 days; three is 120 days.

Does a CDL holder get disqualified for offenses in a personal vehicle? For major offenses, yes. For serious traffic violations, only if the non-CMV conviction results in revocation, cancellation, or suspension of the driver’s license or non-CMV driving privileges (383.51(c)).

Who needs a CDL? Anyone operating a Group A, B, or C vehicle under 49 CFR 383.91 — 26,001 lbs GCWR with a towed unit over 10,000 lbs, 26,001 lbs GVWR single vehicle, or 16-plus passengers including the driver or placarded hazmat. Part 383 applies in interstate, foreign, and intrastate commerce.

How long does a driver have to report a traffic conviction? Thirty days to the employer, in writing (383.31). A suspension, revocation, cancellation, or disqualification must be reported before the end of the business day following the day the driver received notice (383.33).

How many driver’s licenses can a CDL holder have? One (383.21). Employers are separately barred from letting a driver operate while holding more than one (383.37(c)).

Do CDL applicants have to complete entry-level driver training? Yes, for first-time Class A or B CDLs, first-time P or S endorsements, and first-time H endorsements obtained on or after February 7, 2022, from a Training Provider Registry provider (383.71).

Where to go next

Part 383 defines the license; Part 391 defines the file you keep on the driver who holds it, and Part 382 defines the testing program that can take it away. New drivers start at Part 380. Browse the 49 CFR reference library, the DOT compliance guide, or the FMCSA regulations overview. Drivers should start with our driver resources.

This is a plain-English summary of 49 CFR Part 383, not legal advice. Read the current regulation at Cornell LII and consult qualified counsel or your State licensing agency about your specific situation.