Register your entity at sam.gov/register to obtain a Unique Entity Identifier (UEI); the UEI replaced the legacy DUNS number for federal awards. Active registration requires annual renewal.
Request a public API key at open.gsa.gov/api/entity-api/ to access the SAM.gov Entity Management API; the public key tier returns publicly available fields. For FOUO (sensitive) fields, a higher-tier key with additional vetting is required.
Query entity data via GET https://api.sam.gov/entity-information/v3/entities?ueiSAM={UEI}&api_key=YOUR_API_KEY; the v3 endpoint returns JSON with registration, core data, assertions, and points-of-contact sections.
Parse the entityRegistration object for registrationStatus (Active, Inactive, Expired), registrationExpirationDate, ueiSAM, legalBusinessName, and physicalAddress fields.
For supplier onboarding workflows, check registrationStatus=Active and that registrationExpirationDate is in the future before approving a vendor for federal contract payments.
To retrieve multiple entities, use the search parameters (legalBusinessName, ueiSAM as a comma-separated list) and handle pagination via the links.next URL in the response.
Known gotchas
The public API key tier returns only publicly releasable data; fields like banking/EFT information and sensitive points-of-contact require a FOUO-level API key obtained through the GSA Federal Service Desk.
SAM.gov entity registrations expire annually — an entity with a lapsed registration cannot receive federal award payments. Build expiration-date alerting into any supplier management workflow.
UEI values are unique but may be reused after extended inactivity; always pair UEI lookups with legal business name confirmation to detect reuse edge cases.
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