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Invoice due-date calculator

Choose the invoice date and payment term. The calculator adds calendar days and shows the resulting due date.

Calculate the due date

This calculator uses calendar days, including weekends and holidays. Your contract, local rules, or the customer's process may require a different date. No entered information is stored or sent anywhere.

How it works

What does Net 30 mean?

Net 30 generally means payment is due 30 calendar days after the invoice date. Net 7, Net 14, and Net 15 use the same calculation with fewer days. The calculation is:

Due date = invoice date + payment-term calendar days

This calculator counts weekends and public holidays because they are calendar days. It does not apply end-of-month terms, business-day rules, holiday adjustments, late fees, or legal deadlines. Your agreement determines the term you should use.

Net 30 example

1 September 2026 → 1 October 2026

Thirty calendar days are added to the invoice date. September has 30 days, so the result falls on the first day of October.

Net 14 example

20 December 2026 → 3 January 2027

The fourteen-day count continues through weekends and public holidays. Use a different result only when your agreement specifies another rule.

For the complete mobile workflow, read how to create, export, and send an invoice on iPhone.