Architecture Social

Late payment calculator.

Calculate statutory late-payment interest and compensation on overdue invoices under the Late Payment Act.

Late payment calculator.

Free to use — create an account to copy summaries, print clean readouts and unlock extra options. All career tools →

Statutory interest = base rate + 8%. Update when the BoE rate changes.

3 free uses remaining as guest

Total claim

£131

Days late
38
Interest rate
11.75%
Statutory interest
£61
Fixed compensation
£70

Common questions.

Practical answers for the questions people ask about this tool.

What interest can I actually charge on a late invoice?

For commercial debts the statutory rate is 8% above the Bank of England base rate, running from the day payment became late. You can also claim a fixed sum in compensation per invoice, which increases with the size of the debt. These apply unless the contract sets its own substantial remedy.

When does an invoice legally become late?

On the date agreed in the contract. Where nothing is agreed, the default is 30 days from delivery of the goods or service, or from the invoice, whichever is later. Agreed terms longer than 60 days between businesses can be challenged as grossly unfair.

Should I charge interest on a client I want to keep?

The calculation is useful even when you do not invoice for it. Knowing the figure gives you something concrete for the conversation, and stating that statutory interest is accruing often moves a payment on its own. Many practices calculate it, mention it and then waive it as a gesture once paid.

Next steps

Ready to explore roles or pay?

Use these figures as a guide, then browse architecture jobs or check salary bands before making a move.