Late payment interest calculator
Work out the interest that has accrued on an overdue invoice, what each further day of delay costs, and the total now payable. Useful before you send a chase, because a specific number is far harder to ignore than "please settle at your earliest convenience".
Whatever your contract or terms state
Singapore has no statutory late-payment interest rate for ordinary commercial debts, so you can only charge interest your contract or stated terms provide for. Put the rate on your quotation and your invoice, before the debt goes bad.
You can only charge interest your terms provide for
Singapore has no general statutory late-payment interest rate for ordinary commercial debts. That means you may only charge interest if your contract, quotation or stated payment terms provide for it.
The time to add that clause is before you issue the work, not after the debt goes bad. A rate stated plainly on the quotation and repeated on the invoice is enforceable in a way that a rate invented at the chase stage is not.
The daily figure is the persuasive one
Total accrued interest sounds like a penalty and invites argument. The daily figure reframes it: this is what waiting another week costs. It shifts the conversation from whether the charge is fair to when payment will land.
For a business chasing several overdue accounts, that daily number is also how you decide which one to chase first.
Questions
Can I charge interest on late payment in Singapore?
Only if your contract or stated terms provide for it. There is no general statutory late-payment interest rate for ordinary commercial debts in Singapore, so the entitlement has to come from your agreement.
What is a reasonable late payment interest rate?
Singapore SMEs commonly state between 1% and 1.5% per month, which is roughly 12% to 18% a year. What matters more than the exact figure is that it appears on the quotation and the invoice before the debt arises.
How is late payment interest calculated?
Annual rate divided by 365 gives the daily rate, multiplied by the outstanding amount and the number of days overdue. This calculator uses simple interest, not compounding.
A calculator answers one question once. Digital 9 Labs builds the system that answers it continuously — your real numbers, updated as the work happens, without anyone reopening a spreadsheet.