Late invoice interest calculator
See the statutory interest and fixed compensation you're entitled to claim on an overdue commercial invoice.
Interest and compensation owed
Change the dates and amount, the results update instantly.
Statutory interest applies to UK business-to-business invoices only, at 8% plus the Bank of England base rate. Always take advice before acting.
How it works
Under the Late Payment of Commercial Debts (Interest) Act, unpaid UK business invoices accrue simple interest at 8% plus the Bank of England base rate, calculated daily on the days the invoice is overdue. You're also entitled to fixed compensation on top: £40 for debts under £1,000, £70 for debts between £1,000 and £10,000, and £100 for debts over £10,000, without needing to prove any loss.
Frequently asked questions
Does this apply to consumer invoices?
No, statutory interest under this Act applies to business-to-business commercial debts only, not to consumers.
Do I have to claim the interest?
It's your right to claim, but many businesses choose not to for ongoing client relationships. It's a useful lever when payment is significantly overdue, and a common issue for freelancers and contractors chasing invoices from larger clients.
Is the interest compounded?
No, statutory interest under the Act is simple interest, calculated on the original debt for each day it remains overdue.
What is the fixed compensation for?
It's a fixed sum you can claim automatically for the cost of recovering a late debt, without having to prove your actual costs, set by the size of the debt.
Related tools
These results are a simplified illustration based on 2026/27 rates, not advice. Your real position depends on your full circumstances. For a personalised answer, book a free consultation.
Numbers looking complicated?
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