NAICS and PSC Codes: Picking the Right Ones

Federal contracting relies on two separate classification systems that are easy to confuse because both are represented as short numeric codes attached to a contract. One describes the company; the other describes the purchase. Getting both right is what makes a company visible in the searches contracting officers and other companies run, and it is what determines whether a company is eligible to compete on a contract reserved for a particular size or socioeconomic category.

NAICS codes classify the company

The North American Industry Classification System (NAICS) is a standard used across federal statistical and economic agencies, not something invented for procurement. A company selects the NAICS code, or codes, that best describe its business when it registers in SAM.gov, and it selects the single most applicable NAICS code again for each specific solicitation it responds to, since a company operating across several industries may need a different code depending on what a given contract actually calls for.

NAICS codes matter for two distinct reasons. First, government market research tools and many companies searching for potential subcontractors filter by NAICS code, so an inaccurate or incomplete set of codes makes a company harder to find. Second, and more consequentially, the Small Business Administration (SBA) assigns a size standard, either an employee count or an average annual receipts threshold, to every NAICS code. A company's status as "small" for a given procurement is determined entirely by whether it falls under the size standard tied to the NAICS code assigned to that specific solicitation, not by any general notion of company size.

PSC codes classify the purchase

The Product Service Code (PSC) system, maintained by the General Services Administration, describes what the government is actually buying: a category of hardware, a type of service, research and development in a particular field, or a class of supplies. PSC codes appear on every federal contract action reported to the Federal Procurement Data System, and a contracting officer assigns the PSC that best matches the requirement, not the vendor.

PSC codes are the more precise tool for market research on what NASA has actually bought in the past. Searching historical NASA awards by PSC will show, for a given category such as systems engineering support or spacecraft propulsion hardware, which companies have held that kind of work, at what value, and at which center, which is far more actionable than a NAICS code alone.

How the two systems work together in a solicitation

• The contracting officer assigns a PSC describing the requirement itself
• The contracting officer separately assigns a NAICS code, chosen to reflect the industry that predominantly performs that kind of work, along with the associated SBA size standard
• A bidder compares its own size against that size standard to determine whether it qualifies as small for that specific competition, and whether the solicitation is a small business set-aside it is eligible to pursue
• Both codes are recorded on the resulting award and become part of the public procurement record

It is entirely possible for a company that is "small" under one NAICS code and its associated size standard to be "other than small" under a different NAICS code that might also plausibly describe the same work, which is why the code assigned to a specific solicitation, not a company's general self-image, is what governs eligibility.

Choosing NAICS codes strategically

A company should register the NAICS codes that most precisely describe its actual capabilities rather than the broadest codes that might loosely apply, because overly broad codes attract irrelevant search traffic and can misrepresent the size standard a company should be judged against. It is common, and appropriate, to hold several NAICS codes reflecting genuinely distinct lines of business, such as one for engineering services and a separate one for manufacturing, if the company legitimately performs both.

A company can challenge a contracting officer's NAICS code assignment on a specific solicitation if it believes the code, and therefore the size standard, is incorrect for the work being described; this is done through a formal size protest or NAICS code appeal process administered by the SBA, with strict, short deadlines tied to the solicitation's issuance.

Where to look these up

SAM.gov displays and allows selection of NAICS codes directly within a company's entity registration, described in Chapter 2. The current SBA size standards table is published at sba.gov. Historical NASA contract awards, searchable by both NAICS and PSC, along with which center issued them, can be cross-referenced against the center-by-center profile in Chapter 4 to understand not just what NASA buys, but where within the agency it buys it.

A practical starting checklist

1. List every distinct capability the company actually performs, not aspirational ones
2. Match each capability to its most precise NAICS code, not the broadest plausible one
3. Check the current SBA size standard for each code and confirm where the company falls
4. Search historical NASA awards by the corresponding PSC codes to see award history, value, and issuing center
5. Revisit both sets of codes periodically as the company's actual work evolves