DOT number

A DOT number is the unique identifier assigned by USDOT to companies operating commercial vehicles in interstate commerce, used to track safety information.

DOT numbers are issued to motor carriers and certain other commercial vehicle operators. The DOT number is the lookup key in FMCSA SAFER, SMS, and the broader USDOT compliance ecosystem.

A carrier has both a DOT number (vehicle/safety identifier) and an MC number (operating authority). The two are distinct; carriers reference both depending on context.

Why this matters for freight brokers

Carrier lookups for safety rating, CSA scores, and inspection history use the DOT number. Capture it alongside the MC number on every vetting record.

Related terms

• MC number (Motor Carrier number) — An MC number is the operating authority registration number FMCSA issues to motor carriers, brokers, and freight forwarders authorized to operate in interstate commerce.
• FMCSA (Federal Motor Carrier Safety Administration) — FMCSA is the agency within the U.S. Department of Transportation that regulates motor carriers, freight brokers, and freight forwarders operating in interstate commerce.
• SAFER (Safety and Fitness Electronic Records) — SAFER is the FMCSA public-facing carrier lookup system that displays motor carrier registration, operating authority status, insurance, and safety rating.
• SMS (Safety Measurement System) — SMS is the FMCSA public-facing system that displays CSA BASIC percentile scores and alert status for motor carriers.

Sources

• FMCSA SAFER carrier lookup