How the PAYDEX score actually works
Understand Dun & Bradstreet's scoring model and the single habit that moves it the fastest.
PAYDEX is Dun & Bradstreet's payment-performance score. It runs from 1 to 100 and is calculated almost entirely from one input: how many days before or after the due date you pay your invoices, weighted by the dollar value of each invoice. That's it. It doesn't care about your revenue, your industry, or how many tradelines you have — just whether you pay early, on time, or late, weighted by size.
The scale is unintuitive. 80 means 'pays on the due date.' 100 means 'pays 30 days before the due date.' Anything below 80 means you're paying late on at least some accounts. Most lenders and vendors want to see 80+ before they extend meaningful credit, and the best terms open up at 90+.
Because early payments literally score higher than on-time payments, the single fastest way to move PAYDEX is to pay invoices the day they arrive rather than the day they're due. A Net-30 invoice paid on day 2 contributes far more to your score than the same invoice paid on day 30. Vendors don't mind — most actually prefer it — and your score climbs into the 90s within a few reporting cycles.
PAYDEX requires at least three tradelines reporting to D&B before it will generate a score at all. If you check your file and see 'insufficient data,' the fix isn't waiting — it's opening more tradelines. Aim for five reporting accounts as your baseline; that gives the score enough dollar-weighted data to be stable.
One late payment can drop your score meaningfully, and unlike personal FICO, D&B does not 'age out' late marks on a fixed schedule. The score is a rolling weighted average, so late payments get diluted only when they're outweighed by a large volume of newer on-time or early payments. Recovery is possible but slow — much easier to just pay early in the first place.
Practical routine: set every business bill to auto-pay from your business checking account on the day the invoice is received, not the day it's due. Check your D&B file monthly. If a payment isn't reporting, contact the vendor and ask them to submit it — some vendors report only quarterly unless prompted.