Late payment interest calculator UK
Work out the statutory interest you can charge on an overdue business invoice — 8% plus the Bank of England base rate, plus the fixed £40–£100 late payment recovery fee. Free, no signup.
Your invoice
3.75% as of 2026-08 — gov.uk
+ 8% statutory
About this calculator
This calculates statutory interest under the Late Payment of Commercial Debts (Interest) Act 1998, which applies automatically to business-to-business invoices in the UK unless your contract sets a different rate. It's a planning figure, not legal advice — for a debt you intend to pursue formally, get advice specific to your situation.
What it covers
Business-to-business invoices only — the statutory right doesn't apply to consumer invoices. If no payment date was agreed, statutory interest starts 30 days after the client receives the invoice or you deliver the work — whichever is later — so enter that date as the due date above.
TrustSolo tracks overdue invoices for you, so you never have to work this out by hand →
Start freeMore on chasing late-paying clients: your options when a client pays late, and how TrustSolo handles invoicing.