Payment due date calculator

Net 30 means you add 30 days to the invoice date. Net 15 adds 15. Due on receipt is the invoice date itself. The confusion is whether day one is the invoice date or the day after. This page uses invoice date plus the term, which is how most invoicing software counts, and then it shows you the weekday so you can print it.

If your client’s accounts team counts differently, do not spend a week on the philosophy. Ask which date they have in the vendor record, and put that date on the PDF. A shared date beats a won argument about day zero. The wording you paste around the date belongs in the payment terms examples. The choice of Net 15 versus Net 30 belongs in the comparison of those terms. This tool only does the calendar.

What end-of-month terms mean

Larger clients often do not pay ‘30 days from whenever you emailed.’ They pay at month end, or a set number of days after month end, because that is when the payment run exists. EOM on this page is the last day of the invoice’s month. EOM+30 is 30 days after that last day. March’s last day is 31 March even if you invoiced on 4 March. Add 30 and you are in late April, not early April.

If you guess, you will remind them during a window they still call current. They will be right. Use the calculator, write the day on the invoice, and set your reminder schedule from that day rather than from the day you hit send.

Business days, weekends, and the reminder map

Calendar days are the default, because that is what ‘Net 30’ means unless the contract says business days. The weekend toggle is a presentation choice: if the math lands on Saturday, show Monday instead, and say Monday on the invoice. It does not know holidays. You do.

The five reminder dates match the escalation used elsewhere on this site. A note three days before the due date, so the bill is visible before it is late. A nudge the day after. A firmer note at a week, another at two weeks, and a final notice at a month. Copy the schedule into your calendar, or into the payment reminder generator when you need the actual email. The dates are the plan. The email is the execution.

A June invoice, counted out loud

Invoice date Monday 1 June 2026. Due on receipt is 1 June. Net 7 is Monday 8 June. Net 15 is Tuesday 16 June. Net 30 is Wednesday 1 July. Net 45 is Thursday 16 July. Net 60 is Friday 31 July. Net 90 is Sunday 30 August, which the weekend toggle moves to Monday 31 August. The toggle does not change a weekday. It only moves Saturday and Sunday forward. If you wanted a shorter term, change the term. Do not use the weekend switch as a quiet discount.

End of month on that same invoice is Tuesday 30 June, the last day of June, not 30 days after 1 June. EOM+30 is Thursday 30 July, which is 30 days after 30 June. People misread EOM+30 as Net 30. It is not. A client whose vendor master says end of month plus 30 will not pay you on 1 July, and a reminder sent that week will look like you did not read your own terms.

The reminder schedule hangs off the due date you just calculated, not off the invoice date. Three days before, then the day after, then seven, fourteen, and thirty days after. On a Net 30 bill due 1 July, the early note is 28 June, the first overdue note is 2 July, and the final note is 31 July. Copy those five dates. Then write the emails, or generate them, on those mornings. A schedule you do not send is a picture of a process.

What to print, and what to leave off

Print the due date beside the total, in the same size as the total. "Due Wednesday 1 July 2026" is a task. "Net 30" is a riddle you are asking their bookkeeper to solve while they process forty other bills. If their vendor form requires the label, put Net 30 in the terms block as well. Do not put only the label. The wording you paste around it lives in the payment terms examples. This calculator's job is the day.

Leave public holidays off the automatic result. A bank holiday in your country may be a normal Thursday in theirs. If you know they will not pay on a specific holiday, move the printed date yourself and say why in the email, once. Do not build a private holiday calendar into the invoice and then be surprised when their system still shows the original day. One date, agreed, beats two dates you hope they infer.

Custom days are for terms that are real but not in the menu. Net 21, or 10 days from delivery once delivery has a date. Type the number. Do not use custom to mean "about a month," and do not use it to quietly shorten Net 30 to 20 because you are annoyed. If the contract says 30, the calculator should say 30. Changing the math without changing the contract is how a clean chase becomes an argument about the due date instead of the money.

When you have the five reminder dates, put them where you will see them. A calendar, a task list, or the notes on the invoice record. The early one is the one people skip, and it is the one that arrives before the client can honestly say they are late. The last one is a final notice, not a sixth check-in. After that, you are writing a letter, not another email. The payment reminder generator will draft the message for whichever of those five days you are on.

Grace periods sit beside the due date, not instead of it. If you allow seven days before a fee, the invoice is still due on the original day. The fee starts later. Say both dates if you mention a fee. One date for payment, one date for the charge. Mixing them is how a client hears that they had an extra week you did not mean to give.