NAICS Codes

NAICS stands for the North American Industry Classification System. It's a six-digit code that classifies every business establishment by its primary activity. Think of it as the government's way of saying "this contract is for this kind of work."

Every solicitation you issue must include a NAICS code. It tells industry what you're buying and, critically, it determines the size standard — the threshold that decides whether a company qualifies as a small business for that particular contract.

Three reasons, and they all affect you directly:

Here's the practitioner framework. Two rules:

Rule 1: Pick the code that most accurately reflects the requirement. What is the principal purpose of the acquisition? If you're buying janitorial services, don't use a general "facilities support" NAICS just because it's broader. Use the janitorial code.

Rule 2: When more than one code appears plausible, keep working the principal-purpose analysis. Consider the NAICS descriptions, the function of the supplies or services, the relative value and importance of the requirement's components, and which component represents the principal purpose. Do not reverse-engineer the code to create a preferred size standard or competitive outcome.

For services: NAICS codes for services span a wide range. Focus on what the contractor will actually do. IT services, janitorial, engineering, consulting — each has its own series. Search by the function, not by who you think should do the work.

For construction: You're in the 23 series. Construction NAICS codes are broken down by type (general, heavy/civil, specialty trades). Match the code to the type of construction work being performed.

Every NAICS code has a corresponding SBA size standard — usually based on average annual receipts or number of employees. This size standard determines the small business threshold for contracts assigned that NAICS code.

This is why NAICS selection matters beyond just classification: different codes can change which companies qualify as "small." That consequence does not change the selection rule. Pick the single industry that best describes the principal purpose; do not choose a code to manufacture a preferred size standard or competitive pool.

Before you finalize your NAICS selection, you should know what NAICS codes your potential offerors actually claim. Here's how:

Go to SAM.gov and search for the company. In their entity registration, look for their Representations and Certifications. Under the provision 52.219-1 (Small Business Program Representations), you'll find the NAICS codes they've registered under and whether they represent themselves as small for each one.