Just as a credit card company will look at your credit score before issuing you a card, business lenders rely on a similar credit scoring system to determine your ability to borrow money for your business.

A number of business credit reporting agencies have entered the market in the last decade, and new ones continue to pop up, but Paydex from Dun & Bradstreet remains the primary source for business credit scores.

Individual credit scores and Paydex are similar in that both are used to determine whether you get a loan and on what terms. The big difference is that while individual scores take a number of factors into consideration, the Paydex formula looks at only one thing: whether a business makes payments on time and meets creditors' payment terms. That's it.

A Paydex score can range from 0 to 100, with 80 and above "golden." Businesses with a score of 80 meet creditors' terms -- that is, they pay on time. Anything above that means they pay bills before they arrive or during the early payment discount period. A business credit score of 70 means you're paying your bill 15 days late; with a score of 50 you're 30 days late.