Late payment interest calculator
If another business pays you late, UK law lets you claim statutory interest plus a fixed fee. Here is how it works out, and how the app tracks it for you.
What overdue invoices are owed.
Statutory interest is 8% plus Bank Rate. These examples use a Bank Rate of 3.75%, so 11.75% a year, as simple daily interest.
| Invoice | 14 days late | 30 days late | 60 days late |
|---|---|---|---|
| £1,000 | £74.51£4.51 + £70 | £79.66£9.66 + £70 | £89.32£19.32 + £70 |
| £2,800 | £82.62£12.62 + £70 | £97.04£27.04 + £70 | £124.08£54.08 + £70 |
| £5,000 | £92.53£22.53 + £70 | £118.29£48.29 + £70 | £166.58£96.58 + £70 |
| £10,000 | £145.07£45.07 + £100 | £196.58£96.58 + £100 | £293.15£193.15 + £100 |
Each cell shows the total you could claim, then interest plus the fixed fee. Examples only.
How it is worked out
Interest is simple, not compound. For one invoice:
Invoice amount × (8% + Bank Rate) × days overdue ÷ 365
On top of interest, you can claim a fixed fee for each late invoice:
- £40 for a debt under £1,000.
- £70 for a debt of £1,000 to £9,999.99.
- £100 for a debt of £10,000 or more.
Claiming it in practice
- Check your payment terms and the date the invoice was due.
- Send a polite reminder that states the amount owed, the interest to date and the fixed fee.
- Keep a record of every reminder and reply.
- If it still is not paid, take advice on formal steps.
Many clients pay promptly once a reminder includes the figure. Even if you choose not to charge it, knowing what you are owed changes the tone of the conversation.
General information, not legal advice. Check the current Bank Rate and your contract terms before you claim.
Questions, answered.
Does statutory late payment interest apply to every invoice?
It applies to payments between businesses, including sole traders and limited companies. It does not apply to consumers. If your contract sets its own late payment terms, those terms must be a substantial remedy to replace the statutory ones.
When does interest start?
From the day after the payment was due, under the agreed terms. If no date was agreed, the default is 30 days after the invoice is delivered or the goods or services are provided.
Which Bank Rate is used?
The Bank of England Bank Rate in force on 30 June for debts that become due from 1 July to 31 December, and on 31 December for debts that become due from 1 January to 30 June. The examples use 3.75%. Check the current figure before you claim.
Can I claim the fixed fee as well as interest?
Yes. The fixed fee is for the cost of recovering the debt and is added on top of interest, per invoice.
Your score is waiting.
Start in under a minute. Free for life, and no bank connection needed to begin.