What is a UEI?
The Unique Entity Identifier (UEI) is a 12-character alphanumeric code assigned by SAM.gov to every entity that registers to do business with the US federal government. On April 4, 2022, the UEI replaced the DUNS number as the primary federal procurement identifier, ending the 50-year use of Dun & Bradstreet's proprietary DUNS system.
Every active registrant in SAM.gov has a UEI. This includes federal contractors, grant recipients, and entities applying for federal loans or assistance awards. UEIs are assigned automatically during SAM registration — you cannot apply for one separately.
Format: UEIs are exactly 12 characters — a mix of uppercase letters and digits (e.g., HKAMTSE6AAX6). They are not reused — each UEI is unique to a single entity and persists even if the entity's registration lapses.
Why UEI replaced DUNS
The switch from DUNS to UEI was driven by several concerns with the previous system:
- Vendor dependency: The federal government relied on a single private company (Dun & Bradstreet) for a critical government function
- Cost: Obtaining DUNS numbers involved fees for expedited processing and additional data services
- Data control: The government had limited control over DUNS data quality and assignment rules
- Consistency: UEI assignment is now standardized within SAM.gov, improving data quality across federal systems
What a UEI confirms
Looking up a UEI on SAM.gov or KnowVendor returns:
| Data point | What it tells you |
|---|---|
| Registration status | Whether the entity is currently active, inactive, or expired in SAM |
| Legal name | The registered legal name of the entity as on file with SAM |
| Physical address | The address on file — important for identity confirmation |
| CAGE code | The linked CAGE code for the entity (where assigned) |
| Exclusion status | Whether the entity has any active SAM exclusions — see exclusion check guide |
| Entity type | Business type, NAICS codes, and business size classifications |
| Registration expiry | SAM registrations must be renewed annually — an expired registration is a risk signal |
How to find a vendor's UEI
Ask the vendor directly
Any active federal contractor will know their UEI — it is required on every proposal, invoice, and registration renewal. Asking for a UEI is a standard part of vendor onboarding for any organization that does or may do federally-funded work.
Search SAM.gov
Go to sam.gov, select "Entity" search, and search by company name. If the legal name matches exactly, SAM will return the UEI. Note that name-based SAM search can return multiple results for common business names — verify by address or CAGE code.
Search KnowVendor by name or CAGE
If you have a CAGE code, enter it in the KnowVendor search to retrieve the linked UEI and full vendor profile. If you only have a company name, search returns candidate matches with registration status and identifiers shown.
Active vs inactive SAM registration
A UEI existing does not mean the vendor is currently eligible for federal awards. SAM registrations expire annually. A vendor with an inactive or expired SAM registration cannot receive new federal contract awards or payments — even if they were previously registered.
Always check registration expiry date alongside the UEI lookup. For ongoing contracts, contracting officers are required to verify active registration before making payments.
UEI as the foundation for risk screening
A confirmed UEI is the starting point for identity-anchored vendor risk screening. With a UEI, you can reliably link the vendor to SAM exclusion records, USAspending contract history, and other federal data sources without risk of name-matching the wrong entity. Combine UEI with a SAM exclusion check and the due diligence checklist for a complete pre-contract review.