Free Invoice Generator

Invoice due date calculator

Pick the invoice date and the terms, and this works out the day the money is due, in calendar days, in working days or counted from the end of the month.

The invoice

The date on the invoice: the day you issued it, not the day the work ended.

Net 30 means 30 days from the invoice date, not from the end of the job.

How the days are counted

Net terms normally mean calendar days: weekends and public holidays count. Choose working days only if that is what your agreement says.

GuideHow due dates are countedHow this works, and where the figures go wrong →

What the invoice due date calculator does not do

  • It doesn't decide your terms. Net 30 is a convention rather than a legal requirement, and you can ask for shorter terms.
  • It does not know your country's rules on late payment, statutory interest, or what counts as a working day where you invoice. Those vary, and they change.
  • It does not keep anything. Nothing is written to your browser's storage while you use it and nothing is sent to us, so the dates are gone when you close the tab. Press Create this invoice if you need a document: the two dates are handed to the invoice generator in this tab and cleared as soon as it opens.
  • If the invoice editor doesn't offer your term, it sends the due date instead of the term's name. The editor has a shorter list of terms, and the date is what has to carry over.

Related

When the due date has already gone past, the late payment fee calculator takes it from there and works out what the invoice is worth now. For the invoice itself rather than its dates, the invoice calculator takes line items, a discount and a deposit. To add tax to an amount, use the sales tax calculator and the VAT calculator. To turn the term into wording for the invoice and the contract, use the payment terms generator.

Last updated 20 September 2026