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Payment Due Date Calculator

Net 30 sounds precise until you try to write the date on the invoice. End-of-month terms are worse: an invoice issued on the 2nd under EOM plus 30 days is not due in a month, it is due in nearly two. Pick the invoice date and the terms to see the real date, and how long a credit period you have actually granted.

By Arshad Hossain · Published

The short version

  • Net terms run from the invoice date unless the contract says otherwise.
  • End-of-month terms can nearly double the credit period on an invoice issued early.
  • Always print the due date as a date, never as "Net 30".
  • Issuing late moves the due date by exactly as long as you waited.

Payment due date calculator

Net terms run from the invoice date, not from delivery.

Pick the invoice date to see when payment is due.

What Net terms count from

Net terms run from the invoice date by default. Net 30 on an invoice dated the 3rd of March means payment falls due on the 2nd of April. Some contracts instead run terms from delivery, from acceptance, or from receipt of a valid invoice, and each of those pushes the date later.

That last variation matters more than it looks. "30 days from receipt of a valid invoice" lets a client restart the clock by disputing a detail on day 29, which is exactly why large buyers write it that way. If your contract says it, get your invoices right first time.

End-of-month terms

EOM terms treat the end of the invoice month as the starting point. An invoice issued on the 2nd under end-of-month plus 30 days gets 29 days to the month end, then 30 more — 59 days of credit. The same terms on an invoice issued on the 30th give 31.

Buyers like EOM because it lets them run a single payment cycle. It is not unreasonable, but it means the date you invoice within the month materially changes when you get paid. If you are on EOM terms, invoice early in the month only when the work genuinely completed then.

TermsInvoice dated 2 MarchInvoice dated 28 March
Net 301 April27 April
Net 601 May27 May
End of month31 March31 March
EOM + 30 days30 April30 April

Print the date, not the terms

An invoice that says "Net 30" makes the person paying it do arithmetic before they can schedule it. An invoice that says "Due 2 April 2026" can be entered into a payment run without thinking. Print both if you like, but the date is what gets you paid.

It also removes an entire category of dispute. Nobody argues about what a printed date meant, whereas "Net 30" invites a conversation about whether it ran from the invoice, the delivery or the day the invoice reached accounts payable.

Weekends and public holidays

Most terms do not adjust for weekends, so a due date can land on a Sunday. In practice payment runs happen on working days and the money arrives the next one, which is not worth chasing over.

If precision matters — a milestone that unlocks other work, say — write into the contract that a due date falling on a non-working day moves to the next working day. Otherwise expect a day or two of slippage on either side and do not treat it as a late payment.

Payment terms and due dates: common questions

What date is 30 days from my invoice date?

Count 30 calendar days forward from the invoice date, including weekends. An invoice dated 3 March falls due on 2 April. Print that date on the invoice rather than the words, so nobody has to work it out.

Does Net 30 mean 30 working days?

No. Net terms are counted in calendar days, so weekends and public holidays are included. Thirty working days would be about six weeks, which is a materially different arrangement and needs to be written that way.

What does end of month mean on an invoice?

The credit period starts at the end of the month the invoice was issued in, not the invoice date. On EOM plus 30 days, an invoice issued early in a month can carry close to 60 days of credit rather than 30.

When is an invoice actually overdue?

The day after the due date. If payment was due on 2 April, the invoice is overdue on 3 April and any interest you are entitled to starts accruing then, not from the invoice date.

Should I use Net 30 or shorter terms?

Shorter terms generally get you paid sooner, and Net 14 is normal for freelance and small business work. Net 30 is the convention for larger buyers whose payment runs assume it, and pushing against it rarely succeeds.

Frequently Asked Questions

Can I change the terms after sending the invoice?

Not unilaterally. Terms form part of what was agreed. You can agree a change with the client, but reissue the invoice so both records match.

What if I invoice late?

The due date moves out with it, because terms run from the invoice date. Invoicing two weeks after completion delays your payment by two weeks even though the work finished on time.

Does the calculator account for time zones?

Dates are treated as plain calendar dates with no time component, which is how payment terms work in practice.

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