Federal contracting reference
NAICS reference for federal contractors
The top NAICS codes by federal-contracting spend, with the data a small federal contractor actually needs: SBA size standard from 13 C.F.R. § 121.201, set-aside applicability, common FAR / DFARS clause flowdowns, indirect-rate considerations, and links to live USAspending.gov data.
Snapshot date 2026-05-08 (FY2024 reporting period). Each entry links to live federal-obligation data on USAspending.gov.
Professional, Scientific, Technical Services
- 541330over $20BEngineering ServicesSize standard: $25.5 million
- 541512over $20BComputer Systems Design ServicesSize standard: $34 million
- 541511$10B–$20BCustom Computer Programming ServicesSize standard: $34 million
- 541715over $20BResearch and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)Size standard: 1,000 employees
- 541611$5B–$10BAdministrative Management and General Management Consulting ServicesSize standard: $24.5 million
- 541618$1B–$2BOther Management Consulting ServicesSize standard: $19.5 million
- 541310$500M–$1BArchitectural ServicesSize standard: $12.5 million
- 541990$1B–$2BAll Other Professional, Scientific, and Technical ServicesSize standard: $19.5 million
- 541519$2B–$5BOther Computer Related ServicesSize standard: $34 million
- 541620$1B–$2BEnvironmental Consulting ServicesSize standard: $19 million
- 541690$500M–$1BOther Scientific and Technical Consulting ServicesSize standard: $19 million
- 541219$500M–$1BOther Accounting ServicesSize standard: $25.5 million
- 541380$500M–$1BTesting LaboratoriesSize standard: $19 million
Construction
- 236220over $20BCommercial and Institutional Building ConstructionSize standard: $45 million
- 236210$1B–$2BIndustrial Building ConstructionSize standard: $45 million
- 237310$2B–$5BHighway, Street, and Bridge ConstructionSize standard: $45 million
- 237110$1B–$2BWater and Sewer Line and Related Structures ConstructionSize standard: $45 million
- 237990$1B–$2BOther Heavy and Civil Engineering ConstructionSize standard: $45 million
- 237120$100M–$500MOil and Gas Pipeline and Related Structures ConstructionSize standard: $45 million
Specialty Trade Contractors
Manufacturing
- 334511over $20BSearch, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument ManufacturingSize standard: 1,250 employees
- 334290$1B–$2BOther Communications Equipment ManufacturingSize standard: 750 employees
- 334220$1B–$2BRadio and Television Broadcasting and Wireless Communications Equipment ManufacturingSize standard: 1,250 employees
- 336411over $20BAircraft ManufacturingSize standard: 1,500 employees
- 336412$5B–$10BAircraft Engine and Engine Parts ManufacturingSize standard: 1,500 employees
- 336414over $20BGuided Missile and Space Vehicle ManufacturingSize standard: 1,300 employees
- 336992$2B–$5BMilitary Armored Vehicle, Tank, and Tank Component ManufacturingSize standard: 1,500 employees
- 336611over $20BShip Building and RepairingSize standard: 1,300 employees
- 332710$1B–$2BMachine ShopsSize standard: 500 employees
- 332999$500M–$1BAll Other Miscellaneous Fabricated Metal Product ManufacturingSize standard: 750 employees
- 325412$5B–$10BPharmaceutical Preparation ManufacturingSize standard: 1,500 employees
Administrative & Support Services
- 561110$500M–$1BOffice Administrative ServicesSize standard: $12.5 million
- 561210$5B–$10BFacilities Support ServicesSize standard: $47 million
- 561612$2B–$5BSecurity Guards and Patrol ServicesSize standard: $25 million
- 561720$1B–$2BJanitorial ServicesSize standard: $22 million
- 561730$500M–$1BLandscaping ServicesSize standard: $9.5 million
- 561621$500M–$1BSecurity Systems Services (except Locksmiths)Size standard: $25 million
- 561310$100M–$500MEmployment Placement AgenciesSize standard: $31 million
Transportation & Warehousing
- 488510$1B–$2BFreight Transportation ArrangementSize standard: $22 million
- 484110$100M–$500MGeneral Freight Trucking, LocalSize standard: $34 million
- 484121$100M–$500MGeneral Freight Trucking, Long-Distance, TruckloadSize standard: $34 million
- 481111$2B–$5BScheduled Passenger Air TransportationSize standard: 1,500 employees
- 481211$500M–$1BNonscheduled Chartered Passenger Air TransportationSize standard: 1,500 employees
Information & Telecommunications
Waste Management & Remediation
Health Care & Social Assistance
How to use this reference
- Look up your primary NAICS to confirm SBA size standard, set-aside fit, and the FAR / DFARS clauses you should expect on solicitations.
- Cross-reference against current USAspending.gov data using the live links — federal-obligation volumes shift between fiscal years.
- Pair the indirect-rate notes with the Indirect Rate Engine for pool structure and provisional rate tracking that holds up under DCAA review.
- Run the DCAA readiness check against your current accounting setup before bidding on a cost-reimbursable contract under any NAICS listed here.