Users may experience issues verifying ARIZONA commercial driver’s licenses (CDLs) in the Clearinghouse at this time due to system maintenance in Arizona. If this prevents an employer from conducting required pre-employment queries for information on ARIZONA CDL- and CLP-holders only, the employer may hire a driver using solely the procedures set forth in 49 CFR 391.23(e), as outlined in the frequently asked questions.

Also, on Monday, July 20, 2026, from 8 p.m. to 9 p.m. Eastern Time, Clearinghouse users will not be able verify driver CDL information due to FMCSA system maintenance.
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United States Department of Transportation
FMCSA - Federal Motor Carrier Safety Adminstration

Drug & Alcohol Clearinghouse

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Top 6 FAQs

What is the Drug and Alcohol Clearinghouse (Clearinghouse) and what information does it contain?

The Clearinghouse is a secure online database that gives employers, the Federal Motor Carrier Safety Administration (FMCSA), State Driver Licensing Agencies (SDLAs), and State law enforcement personnel real-time information about commercial driver’s license (CDL) and commercial learner’s permit (CLP) holders’ drug and alcohol program violations.

The Clearinghouse contains records of violations of drug and alcohol prohibitions in 49 CFR Part 382, Subpart B, including positive drug or alcohol test results and test refusals. When a driver completes the return-to-duty (RTD) process and follow-up testing plan, this information is also recorded in the Clearinghouse.

Last Updated : January 08, 2020

If a driver has a drug and alcohol program violation in one State, then applies for a commercial driver’s license (CDL) in another State, will the Clearinghouse be able to connect that driver’s drug and alcohol violation history to the new CDL?

Yes. The Clearinghouse will identify drivers who move frequently and obtain CDLs in different States and link those CDLs, in order to maintain complete and accurate information on such drivers.

Last Updated : September 28, 2019

Does the final rule change any of the existing drug and alcohol program requirements in Part 40?

No, the final rule does not change any existing requirements in the U.S. Department of Transportation (DOT)-wide procedures for transportation workplace drug and alcohol testing.

Last Updated : July 22, 2019

How do authorized users sign up to access the Clearinghouse?

Employers, drivers, medical review officers (MROs), substance abuse professionals (SAPs), and consortia/third-party administrators (C/TPAs) must register in the Clearinghouse to access the Clearinghouse.

Instructional job aids are available for:

Employers, C/TPAs, MROs, and SAPs can also invite users to complete required actions in the Clearinghouse on their behalf. These users would register as Clearinghouse Assistants.

Last Updated : December 30, 2019

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test

Last Updated : May 13, 2026

Are CDL drivers required to register for the Clearinghouse?

Drivers are not required to register for the Clearinghouse. However, a driver will need to be registered to provide electronic consent in the Clearinghouse if a prospective or current employer needs to conduct a full query of the driver’s Clearinghouse record—this includes all pre-employment queries.

A driver must also be registered to electronically view the information in his or her own Clearinghouse record.

Registered drivers will have their Clearinghouse accounts and contact preferences set up, allowing them to quickly respond to query requests from employers. Registration is available at https://clearinghouse.fmcsa.dot.gov/register.

Last Updated : January 08, 2020