Late payment is one of the biggest financial challenges facing Nigerian freelancers, SMEs, and contractors. A client who delays payment by 30, 60, or 90 days effectively gets an interest-free loan at your expense. The good news: you have the legal right to charge interest on overdue invoices - and doing so professionally can significantly improve your cash flow.
This guide explains the legal basis, how to calculate late payment interest, and practical steps to enforce your payment terms in Nigeria.
Can You Legally Charge Interest on Late Invoices in Nigeria?
Yes. Under Nigerian contract law, parties are free to agree on penalty clauses and interest charges for late payment. The relevant legal frameworks include:
- The Contracts Act - late payment interest is enforceable if agreed in writing
- FIRS invoicing requirements - do not prohibit late payment charges; they simply require proper documentation
- Common law principles - courts recognise contractual interest provisions
The key requirement is that the late payment terms must be stated in your contract or invoice before work begins. You cannot add a late payment penalty after the fact without prior agreement.
How to State Your Late Payment Terms
Your payment terms should appear in two places:
1. Your Contract or Service Agreement
Include a clause such as:
"Invoices are due within [14/30] days of issue date. Overdue invoices will attract interest at [2–5]% per month (or part thereof) on the outstanding balance until paid in full."
2. Your Invoice
Add a "Payment Terms" section at the bottom of every invoice:
"Payment due: [specific date]. Overdue balances attract interest at 3% per month."
When both the contract and invoice clearly state this, it is fully enforceable.
What Interest Rate Can You Charge?
Nigerian law does not set a fixed maximum late payment interest rate for commercial contracts - parties are free to agree. However, courts may reduce a rate they consider "unconscionable" (grossly unfair). Common rates used in the Nigerian market:
| Rate | Context | |---|---| | 2% per month | Conservative - suits long-standing client relationships | | 3–5% per month | Standard for Nigerian freelancers and SMEs | | 10%+ per month | High - may be reduced by a court if disputed | | CBN MPR + spread | Used in formal financial agreements |
Practical example:
You issued an invoice for ₦500,000 due on 1 February 2026. The client pays on 1 April 2026 - 60 days (2 months) late. At 3% per month:
- Interest: ₦500,000 × 3% × 2 months = ₦30,000
- Total payable: ₦530,000
Types of Late Payment Charges
Percentage Interest (Most Common)
A monthly percentage on the outstanding balance. Compounds if unpaid for multiple months.
Fixed Late Fee
A flat fee added once the invoice becomes overdue. Simple to administer but less deterrent for large invoices.
Example: "A flat fee of ₦5,000 will be added to invoices not paid within 30 days."
Stop-Work Clause
Not a monetary penalty, but highly effective: state that work will be suspended on overdue accounts. This is particularly useful for retainer clients.
Example: "InvoiceGenerator.ng reserves the right to suspend services where invoices remain unpaid beyond 14 days of the due date."
VAT on Late Payment Interest
If you are VAT-registered, be aware: FIRS requires VAT at 7.5% on late payment interest charges when billed to a VAT-able client. Issue a separate invoice or debit note for the interest amount, and include VAT.
Example:
- Late payment interest: ₦30,000
- VAT (7.5%): ₦2,250
- Total debit note: ₦32,250
How to Enforce Late Payment in Nigeria
Step 1: Formal Payment Reminder
Send a written reminder (WhatsApp + email) the day after the due date. Reference the invoice number and due date. Keep the tone professional.
Template:
"Dear [Client], this is a reminder that Invoice No. INV-2026-041 for ₦[Amount] was due on [Date] and remains unpaid. Please arrange payment at your earliest convenience. Interest of [X]% per month applies to overdue balances as per our agreed terms."
Step 2: Late Payment Notice
If unpaid after 7 days, send a formal Late Payment Notice restating the penalty terms and calculating the interest accrued so far.
Step 3: Demand Letter
After 14–21 days, send a formal demand letter (signed, on letterhead) demanding payment of the original invoice plus accrued interest within 7 days, failing which you will pursue the matter legally.
Step 4: Small Claims Court or Arbitration
For amounts up to ₦5 million, Nigeria's Small Claims Courts (available in Lagos, Abuja, Rivers, and other states) offer a fast-track resolution process without needing a lawyer. Filing fees are low and judgments can be obtained in days or weeks rather than years.
For larger amounts or where the contract specifies arbitration, the Lagos Court of Arbitration or Lagos Multi-Door Courthouse offer alternative dispute resolution.
Step 5: Report to Credit Bureaus
Nigerian credit bureaus (CRC, FirstCentral, CreditRegistry) allow businesses to report non-paying commercial debtors. This affects the debtor's credit score and their ability to access financing - a powerful incentive for settlement.
Preventing Late Payment Before It Happens
The best late payment strategy is prevention:
- Collect a deposit upfront - 30–50% before starting work eliminates the worst-case scenario
- Use milestone invoicing - break large projects into payment stages tied to deliverables
- Make payment easy - include a Paystack link on every invoice so clients can pay instantly by card or bank transfer
- Send invoices immediately - do not wait until the end of the month; invoice on delivery
- Know your client - do a basic credit check on new corporate clients; ask for trade references
Create Invoices with Payment Terms Built In
InvoiceGenerator.ng lets you add your custom payment terms, late payment interest clause, and due date to every invoice - professionally formatted and ready to send via WhatsApp or email.
For more on Nigerian invoicing best practices, see our complete invoicing guide and our post on invoice payment terms Nigeria.