Calculate interest on overdue invoices using the South African prescribed rate or a custom rate. See how unpaid debt grows over time and determine the total amount owed.
Calculate exact interest owed on overdue invoices day by day
Uses the current South African prescribed interest rate of 10.5%
Visualise how unpaid debt grows over 12 months
Calculate interest on overdue invoices
Enter your invoice details to calculate late payment interest
Key information about late payment interest in South Africa
The Prescribed Rate of Interest Act (Act 55 of 1975) determines the rate of interest payable on debts where no rate has been agreed upon. The current prescribed rate is 10.5% per annum. This rate is periodically adjusted by the Minister of Justice and published in the Government Gazette.
The prescribed rate applies automatically to any debt that is legally payable and overdue, unless the parties have agreed on a different rate. This includes trade debts, court-ordered payments, and any amount that a court may determine is payable. If your contract specifies a different interest rate for late payments, that contractual rate takes precedence.
Always include clear payment terms on your invoices, specifying the due date and the interest rate applicable to late payments. This protects your right to charge interest and incentivises timely payment. Many businesses use the prescribed rate or a rate slightly above it (where legally permissible) to encourage prompt settlement.
Common questions about interest on overdue invoices in South Africa
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Accounter does not provide accounting, tax, business or legal advice. This calculator has been provided for information purposes only. You should consult your own professional advisors for advice directly relating to your business.