PAYDEX Score: How D&B Calculates It

What is a PAYDEX score?

A PAYDEX score is a Dun & Bradstreet rating from 1 to 100 that shows how promptly a business has paid its suppliers, weighted by the dollar size of each account. The score is built from trade experiences, which are payment records that suppliers and vendors send to D&B, according to Dun & Bradstreet.

A higher number means the business paid faster. Per D&B's scores and ratings page, 80 to 100 is low risk, 50 to 79 is moderate risk, and 0 to 49 is high risk of late payment.

Who reads it? D&B says customers, suppliers, lenders and landlords check a company's PAYDEX rating. They use it to decide whether to work with you, what credit terms to set, what insurance premium to charge and whether to take you on as a tenant.

PAYDEX is one score among several. Our guide to the business credit score covers the other scales and bureaus.

Commera is a broker, not a lender. We compare offers from our lender partners.

How does Dun & Bradstreet turn payments into a score?

Dun & Bradstreet turns payments into a score by giving each payment habit a fixed index value, then averaging those values by dollars. The key below comes from the D&B supplier FAQ.

Source: D&B supplier FAQ, question 1.

The same FAQ lays out the method in three steps:

1. Add up the high credit for each payment class, such as discount, prompt or slow 30.
2. Divide each class total by all high credit dollars to get its share.
3. Multiply each share by the index weight for that class, then add the results.

D&B gives its own example in that FAQ. A business has half its dollars in discount, a quarter in prompt and a quarter in slow 30. The points come out as 45 + 20 + 12.5. D&B prints the last figure as 12 and reports a PAYDEX of 77.

Notice what the method ignores. The number of invoices does not matter. Dollars do.

D&B's PAYDEX infographic says the company can consider up to 875 payment experiences, each from a different supplier.

One caveat applies. According to the document itself, the D&B supplier FAQ carries no date, and its data runs to December 2010.

Per the current D&B PAYDEX page, the score is still dollar-weighted on a scale of 1 to 100. The exact model D&B runs today may differ from the published steps.

Worked example: scoring four supplier accounts the D&B way

In a Commera illustrative calculation, a business with four supplier accounts and $20,000 of high credit lands in the moderate band under the D&B method. Most of its dollars are paid on time, but one account runs late.

Methodology: Commera illustrative calculation using the method published in the D&B supplier FAQ, question 5. It is not the score of a real company, not a forecast and not a promise that any score will change. Each account has one payment class, all experiences fall inside the D&B reporting window, and the business has no other accounts. D&B may calculate differently, for example through rounding rules, the number of experiences it uses or its current model.

This is a credit score illustration, not financing terms, so no rates or payments are shown.

Source: Commera illustrative calculation, index weights per the D&B supplier FAQ.

The total is 75 points. Per D&B, that sits in the moderate risk band.

Read the table from right to left. Packaging carries half the dollars, so it supplies more than half the points. Office supplies pays late too, yet it costs few points because it is small.

What does a business need before it has a PAYDEX score?

A business needs at least three trade experiences, reported by at least two suppliers, before D&B calculates a PAYDEX score. Below that line, the D&B supplier FAQ says the score shows as unavailable.

Three more rules from the same FAQ shape the file:

• Timing: a trade experience counts only if its reported date falls within the last 24 months.
• Updates: the score recalculates when the trade data changes.
• Reporting: payments that suppliers never report cannot be considered, per the D&B PAYDEX page.

Paying a supplier on time does nothing for PAYDEX if that supplier does not send its data to D&B.

Getting a file started is a separate job. Our guide on how to build business credit walks through the D-U-N-S number and opening trade accounts.

Worked example: which late invoice to fix first

Fix the late account that costs the most points first. Under dollar weighting, each account's cost is its share of dollars times the index points it sits below prompt.

Methodology: Commera illustrative calculation that starts from the four accounts in the first worked example and moves one account at a time from its late class to prompt. All other assumptions stay the same. It is not a real company, not a forecast and not a promise of any score change.

Source: Commera illustrative calculation, index weights per the D&B supplier FAQ.

Bringing the equipment repair account to prompt adds six points. The illustrative score reaches 81 and moves into the low risk band. The same fix on office supplies adds one point.

The numbers add up without rounding. Equipment repair holds a fifth of the dollars and sits 30 index points below prompt. Office supplies holds a tenth and sits only 10 points below. Both size and lateness count.

Act on it in order. Rank slow accounts by dollar share times the points they sit below prompt. Clear the top one first.

Does a PAYDEX score matter for a business loan?

Survey data suggest a business score such as PAYDEX plays a smaller part in a business loan than the owner's personal credit. Far fewer firms reported using only a business score than only the owner's personal score, according to the Federal Reserve Small Business Credit Survey.

The 2026 Fed chartbook on firms by gender of ownership groups employer firms by owner gender, and it gives no single figure for all firms. Per that chartbook, 16% of men-owned and 8% of women-owned firms used only a business score. The same chartbook shows 36% of men-owned and 50% of women-owned firms using only the owner's personal score. Both scores were used by 48% of men-owned and 42% of women-owned firms, per the Fed.

Commera's own product page points the same way. According to our business loan options page, the usual profile is "Owner credit usually 650+ for bank terms," with revenue "generally verified from bank statements and tax returns."

So PAYDEX helps with suppliers and with some lenders. The loan decision still rests mostly on your personal credit and your cash flow.

Treat PAYDEX as one part of the file, not the whole file. Our guide to prepare for fast funding shows what underwriters read. When you are ready, check your funding options.

Broker disclosure: Commera Finance is a broker, not a direct lender. Financing providers make their own eligibility, underwriting, approval, pricing, and term decisions.