If you are thinking of doing work for the federal government or applying for a federal grant, you’ll need to have a D-U-N-S number issued by Dun & Bradstreet. This number is the reference number that Dun & Bradstreet assigns to your credit and business file. It’s commonly known as a D & B number.
Most banks and many of your suppliers or vendors will also use your D & B number to pull credit references for your business. If you don’t have a number, you can get one online for free.