Utilities
Convert terms like Net 30, Net 60 or end-of-month into a concrete due date, skipping weekends and holidays where you need to.
Overview
This free payment due date calculator turns terms into a date. Enter the invoice date, choose Net days, end-of-month or on receipt, and it shows the day payment falls due — along with how many days that actually is and how long is left.
The days figure matters more than it looks. Net 30 EOM on an invoice dated the 2nd of the month is fifty-nine days, not thirty, because the clock starts at the month end. Terms that sound similar can differ by a month of cash flow, and the number sitting next to the date is what makes that visible.
Net terms count calendar days, including weekends and public holidays. This is the most common misunderstanding of payment terms anywhere, and it reliably favours whoever misunderstands it least — usually the larger party. If you mean working days, the invoice has to say so.
Non-working days are typed in rather than looked up. A built-in holiday list would have to pick a country, would go out of date every year, and would be trusted anyway — and you already know which days your business does not work. Nothing you type is uploaded; the dates are calculated in your browser and never transmitted.
Step by step
Use the date on the invoice itself, which is often not the date the work finished or the date it was sent.
Net days, on receipt, end of month, or a number of days after the month end. Set what your invoice or contract actually says.
Leave the date alone, roll it forward, or roll it back — and add your own non-working days if you want them skipped.
Background
Payment terms are two decisions wearing one label: how long the buyer has, and what that period is counted from. Almost every dispute about a late payment turns out to be a disagreement about the second one, not the first.
Net terms are the simple case. Net 30 means the full amount is due thirty calendar days after the invoice date — weekends and public holidays included. It is not thirty working days, which would be closer to six weeks, and it is not thirty days from when the work finished. If a supplier wants working days, or the buyer assumes them, that has to be written down, because 'Net 30' will not be read that way by anyone else.
End-of-month terms behave completely differently, and the difference is deliberate rather than an oddity. Under EOM the clock starts at the last day of the invoice month, so every invoice raised in March falls due at the same time regardless of whether it was raised on the 2nd or the 28th. That suits buyers who run a single payment run a month, and it means the effective credit period varies from about thirty days to nearly sixty depending on when in the month you invoice — which is worth knowing before agreeing to it.
The other common construction is an early-settlement discount, written as something like 2/10 Net 30: two percent off if paid within ten days, otherwise the full amount at thirty. That is a discount, not a due date; the invoice is still Net 30. It is also expensive credit when you look at it properly, since two percent for twenty days early works out to a very high annualised rate.
Finally, there is what happens when the date lands on a weekend or a public holiday. There is no universal rule — some contracts roll forward to the next working day, some require the last working day before, and many say nothing at all, in which case the date stands and the buyer decides. It is worth settling in the agreement rather than discovering it on the first month end that falls on a Sunday.
Reference
Four inputs decide the answer, and the disagreements are almost always about the first two rather than about the counting. Nobody argues about what thirty days is; they argue about what it runs from, and about whether it was ever thirty days in the first place.
The invoice date
The date printed on the invoice, which is often not the day the work finished nor the day it was sent. Terms usually run from here, and an invoice raised three weeks after delivery has already spent three weeks of nobody's credit period.
Required
What the period is counted from
The invoice date by default, but some agreements run from receipt of the invoice, from delivery, or from acceptance. Each moves the due date by days or weeks, and it is the single most useful thing to settle in writing before the first invoice.
Required
The number of days
Net 7 for small or new customers, Net 30 as the common default, Net 60 or Net 90 where a large buyer sets the terms. Longer terms are a financing decision as much as a commercial one — you are lending the buyer the money in the meantime.
Required
Whether the terms are end-of-month
Changes the shape of the arrangement rather than just the number. Under EOM the effective credit period depends on where in the month the invoice falls, so invoicing early in a month costs you almost a month of cash.
Optional
Weekend and holiday handling
Roll forward, roll back, or leave it. There is no universal convention, so whichever you use should match the contract. Rolling forward is the more common and the more generous reading.
Optional
Non-working days that apply to you
Public holidays differ by country and often by region, and half-days and shutdowns differ by company. Entering your own is more reliable than any built-in list, which would have to pick a jurisdiction and would go stale each year.
Optional
Any early-settlement discount
Sits alongside the due date rather than replacing it. Record both on the invoice, and be clear that the discount has its own, much shorter, deadline.
Optional
What happens after the due date
Late payment interest, charges or suspension of work. Not part of the calculation, and worth stating on the invoice — terms with no consequence attached are a suggestion rather than a deadline.
Optional
Who it helps
Cash flow is the constraint, and the gap between when work is done and when it is paid is where businesses fail. Knowing the actual date rather than a vague sense of 'end of next month' is what makes chasing possible before it becomes awkward.
Large buyers set the terms, often Net 60 or Net 90 and frequently end-of-month. Working out what that really means before agreeing is the difference between a good contract and one that quietly finances someone else's business.
Chasing works when it starts on the right day. Knowing precisely which invoices are due this week, and which are overdue and by how much, turns collections from a memory exercise into a routine.
A monthly payment run means terms have to be read from the payer's side too. Knowing which invoices genuinely fall due before the next run is what stops suppliers being paid late by accident.
Net 30 is the default for a reason, but it is a choice. Seeing what Net 60 or end-of-month terms actually do to the date is the quickest way to understand what is being agreed to.
The first useful sentence in a chase is the exact date the invoice fell due and how many days ago that was. Both are on this page, and having them removes the hedging from the message.
Do it properly
'Net 30' asks the reader to do arithmetic; a date does not. Printing the actual date removes the most common excuse for late payment and makes any later conversation about it much shorter.
Invoice date, receipt, or delivery — pick one and write it down. This is where nearly every disagreement about lateness starts, and it costs one line on the invoice to prevent.
Under EOM, invoicing on the 2nd rather than the 28th of the same month costs you close to a month of cash for identical work. Even on Net terms, the period does not start until the invoice exists.
Net terms are read as calendar days by everyone. If your terms are in working days the invoice has to say so in words, because no reader will infer it and the difference on a thirty-day term is over a week.
There is no universal rule, so decide it in the contract rather than at the month end. Rolling forward is the common reading, but a supplier assuming forward and a buyer assuming back will disagree every few months.
Late payment interest or a stated charge turns a due date into a deadline. Terms with nothing behind them are treated as a preference, and the businesses that get paid on time are usually the ones that said what happens if they are not.
Chasing works when it is prompt and unemotional, which means it has to be scheduled. Knowing the exact date lets you set a reminder for the day after rather than noticing three weeks later.
Avoid these
Reading Net 30 as thirty working days
It is thirty calendar days, weekends and holidays included. Thirty working days is roughly six weeks, so the two readings differ by a fortnight — and the party who assumed the shorter one is the one chasing.
Assuming Net 30 EOM is thirty days
It is thirty days after the end of the invoice month, so an invoice dated early in a month waits nearly two months. Work out the real figure before agreeing to the terms rather than after the first one falls due.
Counting from the wrong date
Terms usually run from the invoice date, not from when the work finished or when the invoice was opened. Where the contract says otherwise, follow the contract — but make sure it says something, because silence is where the argument starts.
Invoicing late and expecting to be paid on time
The clock does not start until the invoice exists. Three weeks of delay in raising it is three weeks added to the wait, and it is the supplier's delay rather than the customer's.
Putting only the terms on the invoice
Print the due date as well. Asking the reader to work it out invites a different answer from yours, and the difference will not be in your favour.
Treating an early-settlement discount as the due date
2/10 Net 30 is due at thirty days; the ten-day figure is a discount deadline. Confusing the two means either chasing early or offering a discount you did not intend.
Agreeing to long terms without pricing them
Net 90 means financing the buyer for three months. That is a real cost, and it belongs in the price rather than being absorbed silently — particularly for a small supplier where the cash matters more than the margin.
FAQ
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