What Is a D-U-N-S Number?

Sooner or later, a supplier, an app store, or a large customer asks for your D-U-N-S Number. Many new owners have never heard of it. It is a free, nine-digit number that identifies your business in one of the largest business databases in the world, and it is easier to get before you need it than the week someone asks.

What a D-U-N-S Number Is

D-U-N-S stands for Data Universal Numbering System. Dun & Bradstreet, a private company that collects and sells business information, assigns the number. Each business location gets its own nine-digit number, and that number points to a file with details like your legal name, address, phone, industry, and how long you have been operating.

It is not a government number. Your EIN comes from the IRS and is used for taxes. Your state filing number comes from your Secretary of State. A D-U-N-S Number is separate from both, and getting one does not register your business anywhere official. It simply gives other companies a standard way to look you up.

Who Asks for One

You may never need a D-U-N-S Number, or you may need one in your first month. It depends on who you work with. Common reasons include:

• Publishing apps. Apple asks organizations joining its developer program for a D-U-N-S Number to confirm the business is real.
• Large customers and suppliers. Some companies check a D-U-N-S file before they open an account with net payment terms or add you as a vendor.
• Business credit. Dun & Bradstreet keeps a credit file for your business under this number. Some lenders and suppliers look at it.
• Some grants and programs. Certain funders and procurement teams still request it, so it helps to have one ready.

Federal contracts and grants used to require a D-U-N-S Number. Since April 2022, the federal government uses its own Unique Entity ID, issued through SAM.gov, instead. Our SAM.gov UEI service covers that registration.

What Is in Your D-U-N-S File

Your file starts with basic details: business name, address, phone, owners or officers, industry codes, and number of employees. Over time it can grow to include payment history reported by vendors, public records like liens or judgments, and scores Dun & Bradstreet calculates. One of the best known is the PAYDEX score, which runs from 1 to 100 and is based on how promptly a business pays the suppliers that report to Dun & Bradstreet. A score of 80 means bills are being paid on time.

A new business usually has a thin file at first. That is normal. It fills in as you open vendor accounts that report payments and as you keep your details current.

How to Get One

Getting a D-U-N-S Number is free in the United States. The process is short:

1. Search first. Dun & Bradstreet has a lookup tool. Your business may already have a number, especially if it has been around a while or used a vendor that requested one.
2. Gather your details. Use the exact legal name from your formation documents, your business address, phone number, and the name of the owner or officer applying.
3. Request the number on Dun & Bradstreet's website. The free request can take a few weeks. Paid options promise faster processing, but the number itself costs nothing.
4. Save the confirmation and the number with your other business records.

Make sure your name and address match everywhere: your state filing, your IRS records, your bank, and your website. Mismatches are a common reason a lookup fails or an app review stalls. If your legal name is still being decided, the LLC name guide is a good place to start.

One Business, Sometimes More Than One Number

Each physical location of a business can have its own D-U-N-S Number, linked to a main headquarters number. A single-location business usually needs just one. Problems start when a business ends up with duplicates by accident, for example after a move, a name change, or a request made under a slightly different name. Duplicates split your history across two files and can confuse anyone checking you.

Searching before you request a number, and using your exact legal name every time, avoids most of this. If you already have duplicates, Dun & Bradstreet can help merge or correct them.

Keep Your File Accurate

Once you have a number, check your file every so often and after any big change, such as a new address, phone number, or business name. Outdated details can slow down vendor approvals or make it harder for a customer to verify you. Dun & Bradstreet lets business owners view and update their basic company information.

If you are building business credit, the D-U-N-S file is one of several to watch. Experian and Equifax keep their own business files too. Business Banking and Credit, Set Up the Right Way explains how the pieces fit together.

Watch for Look-Alike Offers

Once your business appears in public records, you may get letters or emails that look official and offer to register your D-U-N-S Number, often for a fee. The number itself is free from Dun & Bradstreet. Read any offer carefully and check who sent it before you pay anything. Our D-U-N-S Number service can handle the lookup and request with you if you would rather not do it alone.

It takes a few minutes to request and a few weeks to arrive. Get it before the day someone asks.