NAICS lookup tool

General contractors responsible for the construction (including new work, additions, alterations, maintenance, and repairs) of commercial and institutional buildings and related structures.

Firms that plan and design computer systems integrating hardware, software, and communication technologies. The single most commonly used NAICS code on federal IT services contracts.

Management consulting on strategic and organisational planning, financial planning and budgeting, marketing objectives, and human resource policies. A heavily-used catch-all consulting code in federal procurement.

Application of engineering principles in the design, development, and use of machines, materials, instruments, structures, processes, and systems. Used across civil, mechanical, electrical, and environmental engineering work.

Operating support services for clients' facilities — combinations of services such as janitorial, maintenance, trash disposal, security, mail routing, and reception. Common base-operations contract code.

IT services not classified elsewhere — including computer disaster recovery and software installation. Often used for niche IT work that doesn't cleanly fit 541511 or 541512.

Professional, scientific, or technical services not classified elsewhere — including translation, weather forecasting, and specialised consulting. A frequently-used residual code.

Remediation and cleanup of contaminated buildings, mine sites, soil, or groundwater. The dominant code for federal environmental cleanup work under CERCLA and RCRA.

Specialty trade contractors primarily engaged in installing and servicing electrical wiring and equipment. A core specialty trade for federal building and base contracts.

Cleaning of building interiors, equipment, and windows. One of the most heavily small-business-set-aside codes in federal procurement — most janitorial contracts under $4M are set aside.

Legal services, including law offices providing advice and representation. Federal legal-services awards span outside counsel, expert services, and specialised litigation support.

Accounting services such as billing, bookkeeping, and payroll services — excluding CPA offices. Used for federal financial-management support and contracted accounting work.