Invoice Late Fee Calculator

Calculate penalty charges on overdue invoices

Invoice Amount

Days Overdue

Penalty Type

Penalty Rate / Amount

e.g. 2% per month or flat fee

Late Fee

Total Due

Effective APR

// Standard Rates

Common late fee rates: 1-2% per month, or 18-24% per annum. Some businesses charge a flat fee (e.g., R250) plus interest. Always state terms on your invoice.

// Legal Requirements

Late fee terms must be agreed upfront (in contract or on invoice). You can't charge penalties retroactively. In SA, the Prescribed Rate of Interest Act sets the default at the repo rate + 3.5%.

// Invoice Best Practices

Include payment terms clearly: "Net 30 — 2% late fee per month after 30 days." Send reminders at 7 days, 1 day before, and on the due date.

// Improving Collections

Offer early payment discounts (2/10 Net 30 = 2% off if paid in 10 days). Use automated invoicing. Follow up promptly. Consider requiring deposits for large projects.