Payment terms calculator
Use an invoice date or another agreed starting date to calculate a payment deadline for standard net terms or a custom number of days.
Weekday mode skips Saturday and Sunday, but not public holidays.
Payment due date
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Enter the date from which the payment period begins, choose the agreed number of days, and select calendar days or weekdays. The starting event may be the invoice date, receipt, approval, or another event named in the agreement.
Due date = agreed start date + payment-term days
With calendar-day counting, an invoice dated 1 September with Net 30 terms is due on 1 October.
The invoice issue date is a common starting point, but some customer agreements count from receipt, approval, delivery, or the end of a billing period. Use the event stated in the agreement.
Standard net terms commonly use calendar days. Select weekdays only when the agreement explicitly refers to business or working days, and account for public holidays separately.
The starting date is day zero in this calculator. Net 30 adds 30 complete days, while Due on Receipt returns the starting date itself.
Place the calculated due date on the invoice and keep the same payment terms in the customer agreement, invoice, and related communication.
| Starting date | Terms | Counting method | Due date |
|---|---|---|---|
| September 1, 2026 | Net 30 | Calendar days | October 1, 2026 |
| January 31, 2026 | Net 30 | Calendar days | March 2, 2026 |
| March 6, 2026 | 5 days | Weekdays only | March 13, 2026 |
| December 15, 2026 | Net 30 | Calendar days | January 14, 2027 |
These examples show date arithmetic, not legal advice. Your contract, customer process, and local rules determine the correct starting event and whether weekends or public holidays count.
Identify the date on which the agreed payment period starts, then add the full number of calendar or working days stated in the terms. This calculator treats the starting date as day zero.
No. The invoice date is common, but an agreement may start the period when the customer receives or approves the invoice, when goods are delivered, or at another stated event.
Net 30 commonly means 30 calendar days, but the contract or customer process may specify business days or a different starting event.
No. Net 30 adds exactly 30 days. Adding one calendar month can produce a different deadline because months have different lengths.
Calendar-day mode includes every day. Weekday mode skips Saturdays and Sundays but does not apply country-specific public holidays.
Yes. Choose Custom number of days and enter the term agreed with your customer. The calculator supports terms from 0 to 3,650 days.
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