A late payment interest spreadsheet that picks the rate

No. Your files are read by JavaScript in your browser tab and never sent to us or anyone else. Invoices aren't stored, so closing the tab clears them. Your payment terms and compensation choice can be saved in this browser if you ask; your business name never is.

8% plus the Bank of England reference rate. The reference rate is Bank Rate on 31 December (for interest starting January to June) or 30 June (July to December), and it stays fixed for that invoice. For example, an invoice due in August 2026 uses 3.75% from 30 June 2026, so 11.75% a year.

Simple interest, not compound: amount × annual rate × days late ÷ 365, from the day after the due date to the day it was paid (or the date you choose), rounded to the penny for each invoice.

A fixed sum once per invoice: £40 if it's under £1,000, £70 if it's £1,000 to £9,999.99, and £100 if it's £10,000 or more. You can also claim reasonable extra recovery costs on top, which Latetally doesn't calculate.

When your contract sets its own late payment interest rate, when the customer is a consumer rather than a business, or when the debt is too old (generally six years). Latetally flags old debts but can't read your contract.

Where none was agreed, the default under the Act is 30 days after the later of the customer receiving the invoice or the goods or services. Latetally uses the invoice date plus your default terms (30 days unless you change it), and flags those invoices.

Total interest, compensation and the claim per customer for any number of invoices, every flag, 3 what-ifs and 5 invoices on screen and in print (with a footer). Pro shows every invoice and every what-if and adds a statement for each customer, the Excel workbook and CSV exports.

No. Latetally does the arithmetic from gov.uk's published rules on the invoices you enter. For disputes or court claims, take advice.