See what an overdue B2B invoice is really worth — the statutory interest you can add, the fixed compensation, and the total you can put in a reminder or Letter Before Action.
Interest accrues at the reference rate plus 8% (Late Payment of Commercial Debts (Interest) Act 1998), about £1.61 a day on this debt. Interest and compensation are recoverable from the debtor where the court agrees — RobinReturn takes no cut of either. Figures are illustrative and not legal advice.
On a late UK B2B invoice you can claim statutory interest at 8% above the Bank of England reference rate — 11.75% a year with the reference rate at 3.75% (fixed on 30 June 2026) — plus a fixed sum of £40, £70 or £100 depending on the debt size.
The Late Payment of Commercial Debts (Interest) Act 1998 lets a business add interest and a fixed sum to an overdue commercial invoice. It applies to B2B debts across the UK; RobinReturn covers claims in England and Wales.
Statutory interest is simple interest at 8 percentage points above the reference rate: the Bank of England Bank Rate in force on 31 December (for interest that starts to run from 1 January to 30 June) or on 30 June (for interest that starts to run from 1 July to 31 December). Interest starts to run the day after the payment was due, and the rate fixed at that point applies for the life of the debt.
Interest = unpaid amount × (reference rate + 8%) × days late ÷ 365
Worked example. A £2,400.00 invoice is 60 days late, and the reference rate for its period is 3.75%. The statutory rate is 11.75% a year, so the daily interest is £2,400.00 × 11.75% ÷ 365 = £0.77. Over 60 days that is £46.36. The invoice is between £1,000 and £10,000, so the fixed compensation is £70.00. Total you can claim: £2,516.36.
Fixed compensation under s.5A is a one-off sum per invoice: £40 below £1,000, £70 from £1,000, and £100 from £10,000. It is in addition to the interest.
Both are recoverable from the debtor; if a claim reaches the County Court, whether interest and costs are awarded is at the court's discretion. RobinReturn is not a law firm and does not give legal advice — these figures are illustrative.
The Bank of England Bank Rate fixed for each six-month period — the same table the calculator uses. Last checked: 23 September 2026.
| Interest starts to run | Rate fixed on | Reference rate | Statutory rate |
|---|---|---|---|
| 1 Jul – 31 Dec 2026 | 30 June 2026 | 3.75% | 11.75% |
| 1 Jan – 30 Jun 2026 | 31 December 2025 | 3.75% | 11.75% |
| 1 Jul – 31 Dec 2025 | 30 June 2025 | 4.25% | 12.25% |
| 1 Jan – 30 Jun 2025 | 31 December 2024 | 4.75% | 12.75% |
| 1 Jul – 31 Dec 2024 | 30 June 2024 | 5.25% | 13.25% |
| 1 Jan – 30 Jun 2024 | 31 December 2023 | 5.25% | 13.25% |
| 1 Jul – 31 Dec 2023 | 30 June 2023 | 5.00% | 13.00% |
| 1 Jan – 30 Jun 2023 | 31 December 2022 | 3.50% | 11.50% |
Source: Bank of England Bank Rate history. Check the Bank of England for older periods.
The Late Payment Act guide explains who the Act covers in more detail.
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<p><a href="https://www.robinreturn.co.uk/late-payment-interest-calculator">Late payment interest calculator (UK)</a> by <a href="https://www.robinreturn.co.uk">RobinReturn</a></p>For a B2B debt you can claim statutory interest at 8 percentage points above the Bank of England reference rate under the Late Payment of Commercial Debts (Interest) Act 1998. With the reference rate at 3.75% (fixed on 30 June 2026) that is 11.75% a year, calculated as simple (non-compounding) interest on the unpaid amount.
Yes, for a business-to-business debt. The Act implies the right to statutory interest into the contract, so it applies even if your terms say nothing about late payment. It does not apply to consumer debts, or where the contract sets its own substantial remedy for late payment.
No. The reference rate is fixed on 31 December (for interest that starts to run from 1 January to 30 June) or 30 June (for interest that starts to run from 1 July to 31 December), and that rate applies for the life of the debt.
On top of interest you can claim a fixed sum under s.5A: £40 for debts under £1,000, £70 for debts of £1,000 up to £10,000, and £100 for debts of £10,000 or more. One fixed sum applies per unpaid invoice.
Yes. Statutory interest and the s.5A fixed sum are separate and can be claimed together on the same overdue commercial debt.
No. Statutory interest and the fixed compensation are not payment for a supply, so no VAT is added to them.
No. The interest and compensation are yours. RobinReturn charges only its per-action fees (a reminder is £2.00, a Letter Before Action is £9.50) and takes no percentage of what you recover; a Letter Before Action also carries a £25 review fee plus VAT, paid to the reviewing solicitor, not to RobinReturn.
No. You can state the interest and compensation in a reminder or a Letter Before Action, and many debtors pay before court. If it does reach the County Court, whether interest and costs are awarded is at the court's discretion.
The interest and compensation go in the letter. What that letter costs from a solicitor, a template or RobinReturn.
If the letter is ignored, the same total — debt, interest and compensation — goes on the claim.
The HMCTS issue fee is a fixed sum set by the claim value, not a percentage — and you can add it to your claim.
Five questions to see whether a B2B invoice up to £10,000 fits — no card, no account.
Reminder software chases on a schedule; this takes one overdue invoice to a formal demand, paying per action.
Chasing a slow client on a placement fee or contractor margin while the desk keeps billing.
Recovering a recurring contract invoice without losing the contract.
The Late Payment Act, time limits, evidence, CCJs and the rest of the process in plain English.
Start with a £2.00 reminder that states the debt, interest and compensation — and escalate only if you need to. See how a Letter Before Action works.