Trade payable days: when paying suppliers late costs you more

In short

Trade payable days show how long you take to pay suppliers, and higher is only good within agreed terms. Compare the days you take with the terms for your critical suppliers, and pay those early.

Trade payable days measure the average number of days your business takes to pay its suppliers, usually calculated as average accounts payable divided by cost of goods sold, multiplied by 365. For a small distributor, a higher number is not simply good or bad. It is good while it reflects the credit terms your suppliers agreed to, and bad once it climbs past those terms, because the cash you hold back is paid for in priority, discounts and delivery dates.

What the number actually tells you

The formula is simple. If you carry an average of £60,000 owed to suppliers and your cost of goods sold for the year is £730,000, your trade payable days are 60,000 divided by 730,000, times 365, which is 30 days. Educational references on creditor days make the same point: a business that wants to maximize cash flow should take as long as the terms allow, but taking longer than the terms permit risks lost supplier goodwill and late-payment charges.

The trouble is that the ratio is an average. It cannot tell you whether you pay everyone at day 30 or pay half your suppliers at day 15 and the other half at day 45. It also cannot tell you which of those suppliers you depend on when a customer needs 2,000 branded items in nine working days. A rising figure on a spreadsheet looks like improved working capital. Behind it, it may be a pile of overdue supplier invoices that your best suppliers have already noticed.

What stretching payment really buys

Say you move from paying at 30 days to paying at 60 days across £60,000 of monthly purchases. You hold roughly an extra £60,000 for a month. At an overdraft rate of 10 percent a year, that is worth about £500 a month. That is the real prize, and it is small.

Now look at what sits on the other side of the scale. Suppliers allocate limited capacity in peak season, and the customers who pay on time tend to be the ones whose jobs get slotted in first. Nobody writes this into a contract, but a production manager choosing between two jobs with the same deadline will favor the account that is not 30 days overdue. When a rush order arrives in October for the year-end gifting rush, priority is the only thing that matters, and it is the one thing you cannot buy back at short notice.

> Warning: the cost is invisible until it lands > Lost priority never appears as a line in your accounts. It shows up as a delivery date that moves by three days, then as a customer who does not reorder.

The early payment discount you give up

Many suppliers offer terms such as 2/10 net 30: take 2 percent off if you pay within 10 days, otherwise pay in full by day 30. One finance explainer calculates that taking this discount is equivalent to an annualized return of about 36.7 percent for paying 20 days early. No overdraft costs anything like that.

Run it on £60,000 of monthly purchases. A 2 percent discount is £1,200 a month, or £14,400 a year, against the roughly £500 a month you earned by stretching. The distributor who pays late is not saving money. They are choosing the smaller number. Even if only a third of your suppliers offer a discount, the maths often favors paying those ones early and stretching only the ones that offer nothing.

That is a better use of a payables ledger than a blanket policy. Pay the suppliers who discount or who control your delivery dates promptly. Use the longest legitimate terms with the commodity suppliers you can replace in a day.

Late orders cost more than the cash saved

The largest cost is the one the thesis turns on. Picture a distributor with a £12,000 order for a retail customer, due in stores on a fixed date. The supplier is two weeks behind on payment and puts the order behind three others. The goods arrive four days late. The customer asks for a £1,800 credit, and the distributor pays £900 for air freight to recover two of the days. That one order cost £2,700 and a damaged relationship, which is more than five months of the interest saved by stretching terms.

This is why late supplier delivery is rarely a single failure. It cascades, as we describe in why promotional merchandise suppliers' late deliveries cascade: one slipped date forces a proof, a courier booking and a customer call to be redone. In the promotional merchandise trade, where orders are seasonal and most products are made to order, you depend on a handful of decorators and importers for the fast turns. Those are exactly the suppliers whose goodwill you cannot afford to spend.

How to manage payables without guessing

Treat trade payable days as a per-supplier decision, not a company-wide target.

1. List your top ten suppliers by spend and mark which ones control lead time in peak season.
2. Record each supplier's agreed terms and any early payment discount.
3. Compare the days you actually take with the days agreed. Anything over terms with a critical supplier is a risk.
4. Schedule payment runs around due dates and discount windows, not around when cash feels comfortable.

This is much easier when purchase orders and supplier invoices are matched in one place, so you can see what you owe and when each invoice falls due. A reporting view of aged payables by supplier turns the single average into the list of names that matters.

The takeaway is practical. Keep your average payable days at or just inside your agreed terms, pay your critical and discounting suppliers early, and stretch only where a late payment cannot cost you a delivery. Cash held for a few extra weeks rarely outweighs a missed discount, a lost place in the queue or one late order.

Sources

• Creditor (Payables) Daystutor2u · accessed 2026-10-17
• 2/10 Net 30 Early Payment Discount: Formula & ExamplesHighRadius · accessed 2026-10-17