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The short answer
Yes, if your contract says so: a clear late-payment clause, agreed before the work starts, is what gives you a right to interest from a Nigerian client. Some countries also add interest by statute, such as the UK's 8% above Bank of England base rate on business debts, but that depends on which law governs the contract. Put the rate, the start date and how it is calculated in the contract, and repeat it on every invoice.
The contract does the heavy lifting
A late-payment charge is a term of the deal. If your contract or accepted terms say that overdue amounts carry interest at a stated rate, you can invoice that interest and, if it comes to it, claim it. If nothing was agreed, you are relying on whatever the governing law adds by default, and that is far less certain across borders. We found no Nigerian law that adds UK-style statutory interest to private business invoices, so for Nigerian clients treat the contract clause as the main source of any right to interest.
Which law governs the contract matters for every clause, not just this one. If you have not chosen one, read choosing the governing law with a Nigerian client first.
How the UK statutory scheme compares
For UK-based freelancers it helps to know the default. GOV.UK's late commercial payments guidance, updated 16 October 2026, says:
- If no payment date was agreed, a payment is late 30 days after the customer received the invoice or the service was delivered, whichever is later.
- Statutory interest on business-to-business debts is 8% plus the Bank of England base rate, unless the contract sets a different rate.
- Daily interest is the amount owed times the rate, divided by 365.
- You can also claim a fixed sum per late payment: £40 for debts under £1,000, £70 for £1,000 to £9,999.99, and £100 for £10,000 or more, plus reasonable recovery costs.
- To add interest, send a new invoice for it.
There is a cross-border catch. Section 12 of the Late Payment of Commercial Debts (Interest) Act 1998 says the Act does not apply where a contract is governed by UK law only because the parties chose it, with no significant connection to that part of the UK, and where foreign law would otherwise apply. Whether that bites on a contract between a UK freelancer and a Nigerian client depends on the facts, so do not rely on statutory interest alone; write your own clause.
Writing a clause that holds up
Keep it specific. A workable version:
- Rate: a fixed rate is easier to apply across currencies than a reference rate from one country.
- Simple, not compound, unless you have a reason; it is easier to calculate and less likely to be argued over.
- Start date: the due date, not the invoice date.
- Currency: interest in the invoice currency avoids a second conversion argument.
- Same terms on every invoice: "Late payment interest applies under clause X."
Keep the rate proportionate. A very high rate invites argument that it is a penalty, and a court in either country could refuse it.
Worked example
Example only. A £2,000 invoice under the clause above is paid 45 days late.
- Annual rate
- 12% simple
- Daily interest
- £2,000 × 12% ÷ 365 = about £0.66
- 45 days
- £2,000 × 12% × 45 ÷ 365 = £29.59
- Total due
- £2,029.59, invoiced separately
For comparison, GOV.UK's own example shows £1,000 at a 0.5% base rate building to £85 a year, 23p a day, or £11.50 after 50 days under the statutory scheme.
Before you send an interest invoice
- Check the payment really is late. A SWIFT payment can take several working days, and a Nigerian finance team may have released it already. Ask for the bank confirmation before adding interest.
- Check for a dispute. If the client has raised a written complaint about the work, interest on a disputed amount is harder to justify. Resolve the complaint first.
- Check deductions. A shortfall caused by withholding tax that the client deducted and evidenced with a receipt is not late payment. A shortfall caused by bank charges may be, if your contract says payments are due without deduction.
- Send it as its own invoice, numbered in your normal sequence, quoting the original invoice, days late, rate and calculation, so the client's finance team can approve it as a separate item.
Keep a short log of reminders sent and replies received. If the matter ever goes to mediation or court, a clear record of when the debt fell due and how often you asked is as useful as the clause itself.
Using it in practice
Interest works best as a reason to pay on time rather than a source of income. Many freelancers waive it once, in writing, when a client pays the principal promptly after a reminder, and enforce it with repeat late payers. Combine it with deposits and milestones, covered in upfront deposit terms, and with a steady chasing routine, covered in chasing late payment from abroad.
Where Pryme fits
Pryme Business Accounts come with invoicing and a Finance agent, built by Pryme Intelligence, that prepares reminders and interest invoices from your terms; a person approves before anything is sent, and actions are recorded.
Questions people ask
Can I charge interest on a late invoice to a Nigerian company?
Yes, if the contract says so. Agree the rate, the start date and how it is calculated before the work starts, and repeat it on the invoice.
Does the UK Late Payment Act cover Nigerian clients?
It may, depending on which law governs the contract and the connection to the UK. Section 12 limits it where UK law was chosen only by agreement, so write your own interest clause too.
What interest rate is reasonable?
Choose a fixed, proportionate rate such as 1% a month simple. Very high rates can be challenged as penalties.
How do I actually charge the interest?
Send a separate invoice for the interest, showing the principal, days late, rate and calculation.
Sources
- GOV.UK: Late commercial payments, charging interest and debt recovery (updated 16 Oct 2026) · accessed Oct 2026
- Late Payment of Commercial Debts (Interest) Act 1998, section 12 · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.