Federal contractor registration and IDs
Before a federal agency can award you a contract or pay you for one, your business has to exist in the government's systems. That means one registration and three identifiers, and they are issued together rather than separately.
The order matters. You register in SAM.gov, which assigns your UEI and triggers your CAGE code, and during that registration you choose the NAICS codes that describe your business. Those codes then decide which set-aside opportunities you are eligible for, which is why picking the right primary code is not a formality.
SAM registration
Also: System for Award Management
The free System for Award Management registration every business needs before it can be awarded a federal contract.
SAM.gov is the federal government's central registration system. You cannot be awarded a prime federal contract, or receive payment on one, without an active SAM registration. It is free: no third party is required, and no one should charge you to do it.
Registration captures your UEI, CAGE code, NAICS codes, size and socioeconomic status, banking details, and reps and certs. It must be renewed every year, and letting it lapse can stall an award or a payment, so track the expiration date.
UEI
Also: Unique Entity ID · replaced the DUNS number
The 12-character Unique Entity ID that identifies your business in SAM.gov, now used everywhere the DUNS number used to be.
The Unique Entity ID is a 12-character alphanumeric code that identifies your business across federal award systems. It is assigned in SAM.gov and, since April 2022, has fully replaced the older DUNS number that Dun & Bradstreet used to issue.
Your UEI follows you through registration, proposals, awards, and payment. If a form or portal still asks for a DUNS number, the UEI is what it now wants.
CAGE code
Also: Commercial and Government Entity code
A five-character code that uniquely identifies your business location to the federal government.
The CAGE code is a five-character identifier the Defense Logistics Agency assigns to each physical location a contractor operates from. It ties your company to its records across federal systems, including payment, shipping, and reps and certs.
You do not apply for one separately: a CAGE code is issued automatically when you complete your SAM registration. Businesses outside the United States get an NCAGE code instead.
NAICS code
Also: North American Industry Classification System code
A six-digit code that classifies the kind of work a contract covers, and the industry your business competes in.
Every federal solicitation carries a NAICS code that says what industry the work falls under, from 541511 (custom computer programming) to 236220 (commercial building construction). The code the contracting officer assigns also sets the small-business size standard for that opportunity, measured in either annual revenue or employee count.
You pick the NAICS codes that describe your business when you register in SAM, and they decide which set-aside opportunities you qualify for. Choosing the right primary code matters: it is the first filter buyers and matching tools use to find you.