Data Universal Numbering System (DUNS Number)
A DUNS Number (Data Universal Numbering System) was a unique nine-digit business identifier issued by Dun & Bradstreet to identify companies worldwide. For decades, it served as a foundational identifier in U.S. federal government contracting.
What Is a DUNS Number?
A DUNS Number is a unique 9-digit identifier assigned to a specific legal business entity, linking to that company's business profile. It was widely used in federal procurement systems, with each physical business location eligible to receive its own DUNS number.
Example format: 123456789
Key Characteristics
Unique Identifier: No two businesses share the same DUNS number, ensuring each entity is distinctly identifiable.
Global Recognition: Used internationally for supplier verification and credit tracking.
Linked Business Profile: Connected to a company's legal name, physical address, ownership information, corporate hierarchy, and financial data.
Government Integration: Historically required for federal contractor registration in procurement systems.
Critical Update: DUNS Has Been Replaced
As of April 2022, the federal government replaced the DUNS Number requirement with the Unique Entity Identifier (UEI), issued through the System for Award Management (SAM.gov). The UEI is automatically generated, free, issued directly within SAM.gov, and is no longer managed by Dun & Bradstreet.
However, DUNS numbers may still be required by private sector organizations, for international business verification, and for credit and supplier validation.
Historical Importance in Government Contracting
Previously, contractors needed a DUNS Number to register in SAM, submit federal bids, receive contract awards, and comply with Federal Acquisition Regulation (FAR) clauses. Without a DUNS number, contractors could not compete for federal contracts.
Implications for Government Contractors Today
If You're Registering Now: You need a UEI, not a DUNS number. Registration is handled directly through SAM.gov.
If You Previously Had a DUNS: Your entity was automatically transitioned to a UEI in SAM during the 2022 migration.
If You Work Internationally: Some global institutions and private sector organizations may still request a DUNS number for verification or credit purposes.
Common Misconceptions
DUNS is still mandatory for SAM registration.
It is not. The UEI replaced DUNS in April 2022.
DUNS provides liability protection.
It does not. It is only a business identification number.
Only large companies need a DUNS number.
Historically, all contractors — including small businesses and nonprofits — were required to obtain one.
Frequently Asked Questions
Is a DUNS number still required for federal contracts?
No. It has been replaced by the UEI issued through SAM.gov as of April 2022.
Is the DUNS number the same as an EIN?
No. An EIN is a tax identifier issued by the IRS, while a DUNS number is a business identifier issued by Dun & Bradstreet.
Can a business have multiple DUNS numbers?
Yes. Separate physical locations of the same business could each receive a different DUNS number.
Do I need both a UEI and a DUNS?
Only a UEI is required for federal contracting today. A DUNS number may still be useful for commercial credit or international purposes.
Related Government Contracting Topics
Unique Entity Identifier (UEI): The current standard business identifier for federal contracting, replacing the DUNS number and issued through SAM.gov.
SAM.gov Registration: The System for Award Management, the primary federal database where contractors must register to compete for government contracts.
CAGE Codes: Commercial and Government Entity codes used to identify contractors in federal procurement systems.
FAR Entity Identification Requirements: Federal Acquisition Regulation clauses governing how contractors must identify themselves in federal procurements.
Federal Contractor Compliance: The set of legal and regulatory obligations contractors must satisfy to maintain eligibility in the federal marketplace.
Strategic Importance
The DUNS Number was a long-standing global business identifier created by Dun & Bradstreet and historically required for federal contracting. Today, the UEI has replaced DUNS for U.S. federal contracts, though DUNS may still matter in commercial or international contexts.
Understanding this transition is critical for anyone entering or maintaining eligibility in the federal marketplace. Contractors must ensure their SAM registration is current and reflects their active UEI to remain eligible for contract awards.