Product Service Code (PSC)
A four-character code used by the federal government to identify the products and services being procured — a finer-grained classification alongside NAICS codes.
Definition
Product Service Codes (PSCs), also known as Federal Supply Codes (FSCs), are four-character alphanumeric identifiers maintained by the General Services Administration. PSCs describe what is being bought at a more specific level than NAICS (which describes who is selling). A single NAICS code can map to dozens of PSCs.
When it applies
Federal solicitations on SAM.gov are typically tagged with both a NAICS code and a PSC. Vendors can filter SAM.gov searches by PSC for narrower targeting. Defense contracts make heavy use of PSCs — for example, "D316" is "IT and Telecom — Cloud Computing." NAICS-only searches sometimes miss relevant opportunities, so cross-checking PSC tags is useful.