NAICS Code Quick Reference for Government Contractors

The 50 most common NAICS codes in government contracting. Use these when registering on SAM.gov or searching for contract opportunities.

For a complete guide to how NAICS codes work, see Understanding NAICS Codes.

Construction

NAICS Code	Description	Example Contracts
236220	Commercial and Institutional Building Construction	Office buildings, schools, hospitals
237310	Highway, Street, and Bridge Construction	Road paving, bridge repair
238210	Electrical Contractors	Electrical wiring, panel installation
238220	Plumbing, Heating, and AC Contractors	HVAC installation and repair
238910	Site Preparation Contractors	Excavation, grading, demolition

NAICS Code	Description	Example Contracts
541511	Custom Computer Programming Services	Software development, web apps
541512	Computer Systems Design Services	Systems architecture, network design
541513	Computer Facilities Management Services	Data center operations, managed IT
541519	Other Computer Related Services	Cybersecurity, pen testing, disaster recovery
518210	Data Processing and Hosting Services	Cloud hosting, SaaS, data centers

NAICS Code	Description	Example Contracts
541611	Administrative Management Consulting	Organizational consulting, process improvement
541612	Human Resources Consulting	HR strategy, workforce planning
541613	Marketing Consulting Services	Market research, communications strategy
541618	Other Management Consulting	General consulting, advisory
541990	All Other Professional Services	Specialized consulting NEC

NAICS Code	Description	Example Contracts
541310	Architectural Services	Building design, landscape architecture
541330	Engineering Services	Civil, mechanical, electrical engineering
541620	Environmental Consulting Services	Environmental impact, remediation planning
562910	Remediation Services	Hazmat cleanup, soil remediation

NAICS Code	Description	Example Contracts
621111	Offices of Physicians	Medical staffing, physician services
621999	All Other Miscellaneous Ambulatory Health Care	Health screenings, mobile clinics
621610	Home Health Care Services	In-home nursing, home health aides
339112	Surgical and Medical Instrument Manufacturing	Medical devices, surgical tools

NAICS Code	Description	Example Contracts
561210	Facilities Support Services	Base operations, facility management
561720	Janitorial Services	Office cleaning, custodial services
561730	Landscaping Services	Grounds maintenance, snow removal
561790	Other Services to Buildings	Window cleaning, pest control
562111	Solid Waste Collection	Trash hauling, recycling collection

NAICS Code	Description	Example Contracts
561612	Security Guards and Patrol Services	Guard services, patrol, access control
561621	Security Systems Services	Alarm installation, CCTV, monitoring

NAICS Code	Description	Example Contracts
484110	General Freight Trucking, Local	Local delivery and hauling
484121	General Freight Trucking, Long-Distance TL	Truckload interstate freight
484210	Used Household and Office Goods Moving	Military PCS moves, relocations
485999	All Other Transit and Ground Passenger	Shuttle, NEMT, paratransit
493110	General Warehousing and Storage	3PL, government storage

NAICS Code	Description	Example Contracts
332710	Machine Shops	Precision machining, parts fabrication
334111	Electronic Computer Manufacturing	Computer hardware, servers
334290	Other Communications Equipment Manufacturing	Radio, satellite, networking equipment
336411	Aircraft Manufacturing	Aircraft, unmanned systems

NAICS Code	Description	Example Contracts
611430	Professional and Management Development Training	Leadership training, compliance training
611710	Educational Support Services	Tutoring, test prep, curriculum development

NAICS Code	Description	Example Contracts
541380	Testing Laboratories	Materials testing, quality assurance
541711	Research and Development in Biotechnology	Biotech R&D, pharma research
541715	R&D in the Physical, Engineering, and Life Sciences	Defense R&D, energy research

NAICS Code	Description	Example Contracts
561110	Office Administrative Services	Admin support, office management
561320	Temporary Help Services	Temp staffing, contract personnel
561410	Document Preparation Services	Printing, copying, document management

NAICS Code	Description	Example Contracts
722310	Food Service Contractors	Cafeteria operations, event catering
311999	All Other Miscellaneous Food Manufacturing	MREs, packaged food supply

NAICS Code	Description	Example Contracts
517311	Wired Telecommunications Carriers	Internet service, fiber installation

Find your primary codes. Pick 2-3 NAICS codes that best describe your core business. These go in your SAM.gov registration.
Check size standards. Each NAICS code has an SBA size standard (revenue or employee count). Your small business status depends on the code.
Search by code. On SAM.gov or GovBid, search by NAICS code instead of keywords to find opportunities that match your business classification.
Don't over-claim. Registering under codes you can't support hurts credibility. Add codes as your capabilities expand.

GovBid classifies every tender by industry. Find contracts that match your NAICS codes without manual keyword searching.