About UK Late Payment Calculator
UK business law gives you the legal right to charge interest and a fixed compensation fee when a client pays late on a commercial invoice. The Late Payment of Commercial Debts (Interest) Act 1998 sets the statutory interest rate at 8% per annum above the Bank of England base rate, and adds a fixed compensation fee that scales with the invoice amount. Most UK freelancers and small businesses never claim this because they do not know the exact figures - this calculator works them out instantly.
Enter the invoice amount, the payment due date, and the date payment was actually received (or today if still unpaid). The tool calculates the statutory interest accrued for the number of days overdue, the fixed compensation amount, and the total you are entitled to add to your payment demand or final invoice.
The fixed compensation tiers under the Act are: £40 for invoices under £1,000; £70 for invoices between £1,000 and £9,999.99; and £100 for invoices of £10,000 or more. These are added on top of the daily interest, not instead of it.
Who this is for: UK-based freelancers, contractors, and small businesses chasing overdue commercial invoices. The Act applies to B2B transactions - both parties must be acting in the course of a business. It does not apply to consumer contracts.
Practical use: copy the calculated interest and compensation figures into your overdue payment chasing email or formal demand letter. Quoting the statutory amounts under the Act signals that you know your rights and often prompts faster payment without needing to escalate further. You do not need to include a late payment clause in your original invoice for the statutory right to apply.