Invoice Late Payment Interest Calculator
Instantly calculate statutory interest and fixed compensation on overdue invoices. Free, accurate tool aligned with UK late payment legislation.
Calculate Your Late Fees & Interest
Enter your invoice details below to instantly estimate the statutory interest and fixed compensation you are legally entitled to claim under the UK Late Payment of Commercial Debts (Interest) Act 1998.
Interest Calculator
Enter your overdue invoice details
Total value of the overdue invoice
Days past the agreed payment date
The official dealing rate on the day the debt became overdue (avg: 5.25%)
Estimated Recovery
Based on UK statutory late payment rules
Statutory Compensation Reference Chart
Under UK law, in addition to statutory interest, you are entitled to claim a fixed compensation fee for the administrative cost of recovering the late debt.
| Debt Value | Fixed Compensation | Statutory Interest Rate |
|---|---|---|
| Under £1,000 | £40.00 | Base Rate + 8% |
| £1,000 – £9,999.99 | £70.00 | Base Rate + 8% |
| £10,000 and above | £100.00 | Base Rate + 8% |
Late Payment Interest FAQ
Everything you need to know about claiming statutory interest and compensation on overdue commercial invoices.
Under the Late Payment of Commercial Debts (Interest) Act 1998, the statutory interest rate is 8% plus the Bank of England’s official dealing rate (base rate) that was in place at the end of the day on which the invoice became overdue.
Yes. In addition to statutory interest, you are legally entitled to claim a fixed compensation fee for the cost of recovering the debt: £40 for debts under £1,000, £70 for debts between £1,000 and £9,999.99, and £100 for debts of £10,000 or more.
The formula is: (Invoice Amount × Statutory Interest Rate) ÷ 365 × Number of Days Overdue. For example, a £5,000 invoice 30 days overdue at a 13.25% statutory rate would accrue approximately £54.45 in interest.
No. This calculator is designed for B2B (business-to-business) or business-to-public authority transactions. Late payments from consumers are covered under different legislation, such as the Consumer Rights Act 2015, which has different rules regarding interest and penalties.