Creditor days and debtor days calculator
Enter trade payables, cost of sales, trade receivables and credit sales, and see how long you take to pay suppliers, how long customers take to pay you, and the gap between the two.
Your figures
Take them from your balance sheet and profit and loss for the same period. The days come out on the right.
Your days
Over a 365-day period.
Creditor days - how long you take to pay suppliers
Debtor days - how long customers take to pay you
Cash gap - debtor days minus creditor days
One day of cost of sales
Customers take 16.2 days longer to pay you than you take to pay suppliers. The business funds that gap from its own cash.
£42,000.00 ÷ £380,000.00 × 365 = 40.3 days
£96,000.00 ÷ £620,000.00 × 365 = 56.5 days
The ratio is a year-end average. The overdue invoices are specific.
Zigaflow shows what has been invoiced and what is still outstanding on every job, sends payment reminders automatically, and reads payment status back from Xero or QuickBooks.
See invoicing in ZigaflowThe creditor days formula
Creditor days measures how long, on average, you take to pay your suppliers. It divides what you owe them at the end of the period by what you bought over the period, and scales it to days.
Use credit purchases instead of cost of sales if you have the figure - it is the closer match to what the payables were built from.
With £42,000 owed to suppliers at the year end and £380,000 cost of sales for the year, creditor days are 42,000 ÷ 380,000 × 365 = 40.3 days. The answer is always a positive number of days; a higher number means you are taking longer to pay.
The debtor days formula
Debtor days is the same measure from the other side: how long, on average, customers take to pay you.
Credit sales only - a sale paid up front never becomes a debtor.
With £96,000 owed by customers and £620,000 of credit sales, debtor days are 96,000 ÷ 620,000 × 365 = 56.5 days.
Reading the gap between them
Positive: you pay suppliers before customers pay you. Negative: supplier credit covers the wait.
In the example the gap is 56.5 - 40.3 = 16.2 days. For those 16 days the business has paid for the goods and is still waiting for the customer, so it is funding that stretch from its own cash or an overdraft. Shortening it means collecting faster, agreeing longer supplier terms, or both.
There is no single right number for either ratio. Payment terms differ by trade and by customer, and one late-paying account can move debtor days on its own. Track your own figure over time, and look at the aged debt behind it rather than the average alone.
Related terms
- Creditor days - the definition, and how it relates to supplier terms.
- Debtor days - the customer side of the same measure.
- Aged debt - the invoice-by-invoice view the average hides.
- Cash conversion cycle - the fuller measure that adds stock days.
Chase the invoice, not the average
The ratio tells you there is a gap. Zigaflow shows which jobs are invoiced, which are outstanding and which are paid, with your accounts package kept in step.
- What has been invoiced and what is outstanding, on every job
- Automated payment reminders for overdue invoices
- Invoices exported to Xero or QuickBooks, with payment status read back when the invoice is paid
Questions people ask
Creditor days, debtor days and what the gap between them means.