What Is a DUNS Number? Everything You Need to Know

If you have ever applied for a government contract, registered as an app developer, or tried to establish business credit, you have likely encountered the term "DUNS number." But what exactly is it, who issues it, and do you actually need one? This guide covers everything you need to know about the D-U-N-S Number system.

Definition and History

A DUNS number --- short for Data Universal Numbering System number --- is a unique nine-digit identifier assigned to a single business entity. It was created by Dun & Bradstreet (D&B) in 1963 to help track and organize business information across its commercial database.

Dun & Bradstreet itself traces its roots back to 1841, making it one of the oldest commercial data companies in the world. The DUNS system was introduced to solve a fundamental problem: how do you reliably identify one business and distinguish it from every other business on the planet? Before the DUNS number, companies were often confused with similarly named entities, subsidiaries were mixed up with parent companies, and there was no universal standard for business identification.

Today, the D&B database contains records for over 500 million businesses worldwide, and the DUNS number has become a de facto global standard for business identification. It is recognized and required by the United Nations, the U.S. federal government, the European Commission, and major corporations around the world.

How the 9-Digit System Works

Each DUNS number is a non-indicative nine-digit number. "Non-indicative" means the digits themselves carry no embedded meaning --- unlike, say, a ZIP code where the digits correspond to a geographic region. The number is simply a random, unique identifier tied to a specific business location.

Key characteristics of a DUNS number:

Unique: No two entities share the same number.
Location-specific: A company with three office locations would have three separate DUNS numbers, one for each physical site.
Persistent: Once assigned, the number stays with that business entity permanently, even if the company changes its name.
Non-transferable: You cannot sell, give away, or reassign your DUNS number to another entity.

For example, a DUNS number looks like this: 08-146-6849. The format is simply nine digits, sometimes displayed with hyphens for readability.

Who Issues DUNS Numbers?

Dun & Bradstreet is the sole issuer and maintainer of DUNS numbers. No government agency, trade association, or other third party assigns them. D&B operates the system as a proprietary service, though obtaining a basic DUNS number is free for businesses.

D&B maintains the associated business data --- including company name, address, phone number, number of employees, industry classification, and corporate family structure --- in their commercial database. This data feeds into D&B's business credit reports and risk assessments, which are widely used in commerce and lending.

Who Needs a DUNS Number (and Who Doesn't)

You Likely Need a DUNS Number If You:

Apply for U.S. federal grants or contracts: Registration in SAM.gov (System for Award Management) requires a DUNS number. This applies to nonprofits seeking federal grants as well.
Publish apps on Apple's App Store: Apple requires a DUNS number for organizations enrolling in the Apple Developer Program.
Want to build business credit: D&B's Paydex score and credit reports are tied to your DUNS number. Lenders and suppliers often check it.
Work with large corporations: Many Fortune 500 companies require suppliers and vendors to have a DUNS number as part of their onboarding process.
Bid on contracts internationally: The European Commission and United Nations use DUNS numbers for vendor identification.
Register for Google Developer accounts: Organizations registering for Google developer programs may need one.

You Probably Don't Need One If You:

You are a sole proprietor or freelancer with no plans to seek business credit, government contracts, or corporate vendor relationships.
You operate a small local business that deals only with individual consumers.
You are an individual (DUNS numbers are for business entities, not people).

For a deeper look at why small businesses benefit from having one, see our guide on DUNS numbers for small business.

DUNS Number vs. Other Business Identifiers

Business owners often confuse the DUNS number with other identification numbers. Here is how they compare:

Identifier	Issuer	Purpose	Digits	Cost
DUNS Number	Dun & Bradstreet	Business identification & credit reporting	9	Free
EIN (Employer Identification Number)	IRS	Tax identification	9	Free
SAM UEI	SAM.gov / GSA	Federal procurement identification	12 characters	Free
State Business ID	State government	State registration & compliance	Varies	Varies
LEI (Legal Entity Identifier)	GLEIF-accredited issuers	Financial transaction identification	20 characters	~$70--$200/year

The most common mix-up is between a DUNS number and an EIN. The key difference: an EIN is for tax purposes (issued by the IRS), while a DUNS number is for business credit and identification (issued by D&B). They serve completely different functions, and having one does not replace the need for the other. For a detailed comparison, read DUNS Number vs. EIN: What's the Difference?

How to Get a DUNS Number

Getting a basic DUNS number is free. Here is the process:

Check if you already have one. Many businesses are assigned a DUNS number automatically based on public records. Use our free DUNS lookup tool to search before applying.
Apply through D&B's website. Visit the Dun & Bradstreet website and request a DUNS number. You will need to provide your business name, address, phone number, legal structure, and the name of the business owner or principal.
Wait for processing. The standard free process takes up to 30 business days. D&B verifies the information you submit before issuing the number.
Consider expedited processing. If you need your number faster, D&B offers paid expedited options that can deliver your DUNS number in as little as 1--5 business days.

For a complete walkthrough, visit our how to get a DUNS number guide. If you are wondering about timing, see how long it takes to get a DUNS number.

How to Look Up a DUNS Number

If you need to find an existing DUNS number --- whether your own or another company's --- there are several ways:

Use our free lookup tool. The fastest option: enter a company name on our DUNS number lookup page and get results instantly.
Search on D&B's website. Dun & Bradstreet offers a business search tool on their site, though some features require a paid account.
Check SAM.gov. For entities registered for federal contracting, SAM.gov's entity search displays DUNS numbers in public records.

To learn more about your options, read our full guide on how to look up a DUNS number for free.

Understanding DUNS Number Data

When you look up a DUNS number, the record typically includes:

Business name (legal name and any trade names / DBAs)
Physical address of the business location
Mailing address (if different)
Phone number
Number of employees (at that location and company-wide)
Annual revenue (estimated or reported)
Year established
Industry classification (SIC and NAICS codes)
Corporate family tree (parent company, subsidiaries, branches)

This data is what feeds into D&B credit reports and risk scores. Keeping it accurate is important --- if your information is outdated, it can affect your business credit profile and your ability to win contracts.

Frequently Asked Questions

Is a DUNS number the same as a tax ID?

No. A DUNS number is issued by Dun & Bradstreet for business identification and credit reporting. A tax ID (EIN) is issued by the IRS for tax purposes. They are separate numbers that serve different functions.

Does getting a DUNS number cost money?

A basic DUNS number is free. D&B charges for expedited processing and for premium services like credit monitoring and detailed business reports.

Can an individual get a DUNS number?

DUNS numbers are assigned to business entities, not individuals. However, sole proprietors operating under a business name can obtain one.

How long is a DUNS number valid?

A DUNS number does not expire. Once assigned, it remains with that business entity permanently. However, D&B may deactivate records for businesses that have closed.

Can I have more than one DUNS number?

Each distinct business location gets its own DUNS number. So a company with a headquarters and two branch offices would have three DUNS numbers. But a single location should only have one.

What happens to my DUNS number if I change my business name?

The DUNS number stays the same. You will need to update your information with D&B, but the number itself does not change.

Is a DUNS number required by law?

There is no law requiring all businesses to have a DUNS number. However, it is effectively mandatory for certain activities, such as registering in SAM.gov for federal contracting or enrolling in Apple's Developer Program.

Ready to find your DUNS number? Use our free DUNS number lookup tool to search now, or learn about the benefits of having a DUNS number.