Abbreviation: DOT Number

USDOT Number

A unique identifier assigned by FMCSA to carriers and certain other entities subject to its safety regulations. Required for interstate commercial motor vehicle operations above FMCSA thresholds.

Carriers with a USDOT number must comply with FMCSA regulations, including DQ file requirements, drug/alcohol testing, and Clearinghouse obligations.

Related: fmcsa , owner operator , mc number , operating authority

Last updated: June 4, 2026