Understanding the NAICS System

Two digits: Economic sector (e.g., 54 = Professional, Scientific, and Technical Services)
Three digits: Subsector (e.g., 541 = Professional, Scientific, and Technical Services subsector)
Four digits: Industry group (e.g., 5415 = Computer Systems Design and Related Services)
Five digits: NAICS industry (e.g., 54151 = Computer Systems Design and Related Services)
Six digits: National industry - most specific level (e.g., 541511 = Custom Computer Programming Services)

Selecting Your NAICS Codes

1
Analyze your service delivery
Document what your company actually does, breaking services into distinct categories. Consider past projects and how you would describe them to a potential customer unfamiliar with your business.
2
Review the NAICS manual
Read the official descriptions for codes you're considering at census.gov/naics. The descriptions include examples of activities included and excluded from each code, helping you identify the best fit.
3
Research competitor profiles
Look at SAM.gov profiles of companies with similar capabilities. See which NAICS codes they selected, but remember their business mix may differ from yours.
4
Analyze contract opportunities
Search SAM.gov for contracts you would want to win. Note which NAICS codes agencies assign to those opportunities—this reveals how buyers think about the work.
5
Consider size implications
Different NAICS codes have different size standards. Understanding how your size measures against each code's threshold may influence which opportunities you pursue.
6
Validate with a PTAC counselor
Procurement Technical Assistance Centers offer free guidance on NAICS selection. Their counselors can help verify your choices align with federal buyer expectations.

Selecting based on aspirations rather than capabilities: Choose codes that reflect what you actually do and can demonstrate, not what you hope to do someday
Ignoring size standard implications: A code might describe your work perfectly but use a size standard under which you're other-than-small
Copying competitors blindly: Just because another company uses a code doesn't mean it's appropriate for your different service mix
Missing the sixth digit: Some contractors stop at five digits, but six-digit codes provide the specificity that matters for many procurements
Selecting too many codes: Listing a dozen codes suggests lack of focus and makes it harder for buyers to understand your core capabilities
Never updating selections: Your business evolves—review and update NAICS selections annually to ensure alignment with current capabilities

541511 - Custom Computer Programming Services: Writing, modifying, testing custom software to meet user needs. Size standard: Employee-based with a $34 million threshold.
541512 - Computer Systems Design Services: Planning and designing computer systems integrating hardware, software, and communications. Employee-based with a $34 million threshold.
541513 - Computer Facilities Management Services: On-site management and operation of client computer systems. Employee-based with a $34 million threshold.
541519 - Other Computer Related Services: Computer-related services not elsewhere classified, including disaster recovery and software installation. Employee-based with a $30 million threshold.
518210 - Data Processing, Hosting, and Related Services: Data processing, hosting, streaming, application hosting. Revenue-based with a $40 million threshold.
541715 - Research and Development in the Physical Sciences: R&D in physical and life sciences, including IT research components. Employee-based with 1,000 employee threshold.

541611 - Administrative Management Consulting: Advice on administrative management issues like strategic planning, financial planning, human resources. $24.5 million revenue threshold.
541612 - Human Resources Consulting: HR consulting, compensation analysis, benefits consulting, executive search. $34 million revenue threshold.
541614 - Process, Physical Distribution, and Logistics Consulting: Advice on manufacturing processes, logistics, supply chain optimization. $19 million revenue threshold.
541618 - Other Management Consulting: Management consulting not elsewhere classified. $19 million revenue threshold.
541330 - Engineering Services: Civil, electrical, mechanical, structural engineering design and consulting. $25.5 million revenue threshold.
541620 - Environmental Consulting: Environmental impact assessments, remediation planning, regulatory compliance consulting. $19 million revenue threshold.

List primary NAICS first, followed by secondary codes in order of relevance to your business focus
Include keywords in your capability narrative that match how agencies describe work in your areas
Keep certifications current—expired certifications undermine credibility even if underlying qualifications remain valid
Update past performance information to reflect current capabilities and recent contract experience
Verify contact information accuracy so agencies and prime contractors can reach you easily
Review your profile quarterly to ensure information remains current and competitive