Department of Transportation NAICS 561621 contractors

Security Systems Services (except Locksmiths). Contractors in this NAICS lane under Department of Transportation.

Agency: Department of Transportation

Last updated: April 8, 2026

Visible recipients

Mapped obligations

$1,376,022,240

Visible recipients tied to Department of Transportation and NAICS 561621

Serco INC

Herndon, VA

Herndon, VA | 1,016 awards | Top agency Department of Defense | NAICS 541330

M. C. Dean, Inc.

Tysons, VA

Tysons, VA | 1,299 awards | Top agency Department of Defense | NAICS 541330

The Whitestone Group, Inc.

Reynoldsburg, OH

Reynoldsburg, OH | 67 awards | Top agency Department of Transportation | NAICS 561612

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