Business calculator
Free Invoice Due Date Calculator
Calculate an invoice due date from the invoice date and payment terms.
Invoice Due Date Calculator
Invoice due-date guidance
Translate payment terms into a calendar date
Net terms describe how many days a customer has to pay after the invoice date. This calculator treats the date as a calendar date, so month boundaries and leap years remain predictable.
Due on receipt
This adds zero days, so the due date is the invoice date.
Net 30
Net 30 means payment is due 30 calendar days after the invoice date.
Calendar-safe math
The tool adds days locally without UTC date parsing that can shift the day.
No late fees
Late charges are intentionally separate; use the late-fee calculator for that estimate.
How to use this calculator
Choose the invoice date and payment term
- 1
Set invoice date
Use the date shown on the invoice, not the date you happen to open the calculator.
- 2
Choose terms
Select due on receipt, a net-day preset, or enter custom days.
- 3
Review the due date
Use the result to check the invoice and payment instructions before sending.
What Net 30 and Net 60 mean
Net 30 generally means the full amount is due 30 calendar days after the invoice date. Net 60 uses 60 days, and the same pattern applies to the other presets.
Always follow the terms in your agreement if they define business days, month-end rules, holidays, or a different starting point.
Invoice date versus due date
The invoice date identifies when the billing document was issued. The due date is the resulting payment deadline. Keeping both visible reduces ambiguity for the customer and your own records.
Calendar-day assumptions
This calculator adds whole calendar days and handles month boundaries and leap years. It does not determine banking holidays or whether a contract shifts deadlines that land on a non-business day.
Example: Net 30
Invoice date: September 21, 2026 Payment terms: Net 30 Due date: October 21, 2026 Due on receipt would keep the due date at September 21, 2026.
Common mistakes to avoid
- Parsing a date through UTC and accidentally showing the previous day.
- Using the send date when the agreement uses the invoice date.
- Assuming Net 30 always means the end of the following month.
- Adding late fees here instead of checking the separate late-fee policy.
Frequently asked questions
Practical questions people ask about this tool
Does Net 30 mean 30 business days?
Usually Net 30 means 30 calendar days, but your contract or payment policy may define a different convention.
What does due on receipt mean?
It means the payment date is the same as the invoice date in this calculator.
Does the calculator handle leap years?
Yes. It uses calendar-date arithmetic, including month boundaries and leap-year dates.
Does it calculate late fees?
No. It only calculates the due date. Use the Invoice Late Fee Calculator for a separate arithmetic estimate.
Related tools
Connect due dates with the billing workflow
Invoice Generator
Create an invoice with dates and payment terms.
Invoice Late Fee Calculator
Estimate a late charge after an invoice is overdue.
Quote Generator
Set expectations before the invoice stage.
Your generated document stays clean: no ads or forced watermark in the finished output. Use the tool first, then review the supporting guidance below only when you need the extra context.