NAICS Codes for Federal Contracts Explained

What a NAICS code is

The North American Industry Classification System (NAICS) is the standard the United States, Canada and Mexico use to classify businesses by industry. In the US it is maintained under the Office of Management and Budget and published by the Census Bureau, and it is revised every five years. Federal contracting borrows it to label both businesses and contracts.

Codes run from two to six digits, and each extra digit narrows the industry:

Federal solicitations and SBA size standards use the full six-digit code. Some sectors span a range of two-digit codes, such as 31-33 Manufacturing.

How agencies assign a NAICS code to a notice

The contracting officer chooses the code that best describes the principal purpose of what is being bought and records it on the solicitation. Under FAR Part 19, that choice also fixes the size standard for the contract. A solicitation normally carries one NAICS code; multiple-award contracts can assign different codes to different parts of the requirement.

The code reflects the work, not the agency or the bidder. A construction contract at a hospital is coded as construction, and an IT help desk for the Army is coded as IT services. On CapitolBids you will find the code on every notice page, linked to its industry page.

Size standards: why the code matters

SBA sets a size standard for each six-digit NAICS code, published in 13 CFR 121.201. A size standard is either a maximum average annual receipts figure or a maximum average number of employees, depending on the industry. Many service industries use receipts; most manufacturing industries use employees. A business is small for a code if it falls under that code's standard, counting its affiliates as SBA's rules require.

The size standard on a solicitation is what matters for a set-aside: to compete for a small business set-aside you must be small under the code the agency chose, not just under your own primary code. Size standards are reviewed and adjusted periodically, so look them up on SBA's size standards tool rather than relying on a figure you saw once.

How to choose your NAICS codes

1. Start from your work. Search the Census NAICS lookup for the services or products you provide and read the definitions, not just the titles.
2. Check what agencies use. Search federal opportunities for the kind of work you do and note the codes on the notices. Agencies sometimes code similar work differently, and you want to be findable under the codes they actually use.
3. List every code you can perform. SAM.gov lets you list several codes with one marked primary. Include each code where you could credibly deliver, and leave out codes you could not.
4. Check the size standard for each. Your small business status, and so your access to set-asides, is decided code by code.

NAICS codes and Product and Service Codes

Federal contract records also carry a Product and Service Code (PSC), a four-character code describing what was bought. Product codes are numeric and service codes begin with a letter; for example, R408 is program management and support services. The PSC Manual lists them. PSCs do not set size standards, but they are a useful second filter: a NAICS code tells you the industry, a PSC tells you the purchase.

Using NAICS codes on CapitolBids

• The NAICS hub lists federal opportunities by industry, from two-digit sectors down to six-digit codes, with counts of open notices.
• Search accepts a NAICS code or prefix: enter 5415 to cover every code beginning 5415, or a sector range such as 31-33. A PSC filter sits alongside it.
• With a free account, email alerts can watch your NAICS codes so new notices in your industry arrive by daily or weekly digest.