Free calculator
Invoice due date calculator
Pick the invoice date and your payment terms. You get the due date, and whether it falls on a weekend.
Due date
31 October 2026
- Day of the week
- Saturday
- Days from the invoice date
- 30
This is a weekend: many businesses pay on the next working day.
Make an invoice with these termsPayment terms in South Africa
- 30 days from the invoice date is the most common term.
- “30 days from statement” counts 30 days from the month-end statement: an invoice dated 15 September is due on 30 October.
- There’s no law setting payment terms between businesses: you agree them with your client.
Last updated 2026-10-01. This calculator is a guide, not tax advice.
Frequently asked questions
What does “30 days from statement” mean?
Many South African businesses send a statement at month end; payment is due 30 days after it. Every invoice from one month falls due on the same day.
Can I charge interest when an invoice is late?
Business clients owe interest at the prescribed rate unless you agreed another. Consumers only if they accepted it upfront.
Does 30 days count weekends?
Yes: payment terms count calendar days. If the due date falls on a weekend or public holiday, many clients pay on the next business day.