What can I claim on an unpaid invoice?
When a business customer doesn't pay on time, you're entitled to charge interest on the money — and most people never do. Statutory interest under the Late Payment of Commercial Debts (Interest) Act works out at 8% above the Bank of England base rate, plus a fixed sum towards the cost of chasing the debt.
On a £1,800 invoice that's been sitting for six weeks, that's usually north of £80 you're owed on top of the job. It's not a favour you're asking for; it's the legal default when a commercial customer pays late and you haven't agreed different terms.
The important detail is that the rate is fixed on the day the debt arose, not today — so put in the base rate that applied back then.
Not sure how much of this is worth chasing? Check the job profit calculator — interest quietly eaten by an overdue invoice is one of the fastest ways a profitable job turns into a loss.
The base rate is the one that applied on the day the debt arose, not today's rate — that is the moment the statutory rate is fixed. Check the current figure on the Bank of England website if you are not sure.
This is a guide to the statutory calculation, not legal advice, and it assumes the debt is a commercial one with no agreed contractual rate of its own.
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