How do UEI and CAGE codes work in entity validation?

How do UEI and CAGE codes work in entity validation?

SAM.gov says you can either complete a registration to bid on government contracts and apply for federal awards, or request only a Unique Entity ID without completing a registration. If you want to apply for federal awards as a prime awardee, you need a registration, and SAM.gov assigns the Unique Entity ID as part of that process. The same guidance says entities that only conduct certain transactions, such as reporting as a sub-awardee, may not need a registration.

FAR Subpart 4.18 treats the Commercial and Government Entity code as a separate identifier used to identify entities and support data exchange, unique identification, and ownership-or-control checks. It also states that the unique entity identifier is a different identifier. Before award above the micro-purchase threshold, offerors must provide the contracting officer the CAGE code assigned to the offeror’s location when SAM registration or a UEI is required in the solicitation. Contracting officers verify CAGE by reviewing the SAM registration; active registrations have verified CAGE codes. If the entity is not required to be in SAM, the contracting officer validates the CAGE code through the DLA CAGE search site.