How to Calculate Net 30, Net 45, and Net 60 Due Dates

An invoice arrives stamped "Net 30" — so when, exactly, is the money due? It's one of the most common questions in small-business bookkeeping, and the stakes are real: pay late and you strain a supplier relationship or trigger late fees; chase a client too early and you look disorganized. The good news is that net payment terms are simple date math once you know the three rules hiding behind them.

Quick summary: Net 30, Net 45, and Net 60 mean full payment is due 30, 45, or 60 calendar days after the invoice date. Count every day — weekends and holidays included. An invoice dated September 1 on Net 30 terms is due October 1. To find any due date instantly, put the invoice date into our Date Add/Subtract Calculator and add the net period in days.

What "Net" Actually Means

The "net" in Net 30 means the net amount — the full invoice total after any discounts — is due within that many days. The count almost always starts from the invoice date, not from when you received the invoice or when the goods arrived (though some contracts define it differently, which is why the fine print always wins — more on that below).

Net 30 is the most common rhythm of business-to-business trade in North America. Net 45 and Net 60 are common with larger companies, whose accounts-payable departments batch payments on longer cycles. You'll also see Net 15 for faster turnaround and Net 90 at the slow extreme.

Calculating the Due Date: A Worked Example

Take an invoice dated Tuesday, September 1, 2026.

Net 30: count 30 calendar days forward. September has 30 days, so the due date is Thursday, October 1, 2026.

Net 45: 45 days forward lands on Friday, October 16, 2026.

Net 60: 60 days forward lands on Saturday, October 31, 2026 — a weekend, which raises the obvious question.

What If the Due Date Falls on a Weekend?

There's no universal rule. The most common convention is that payment is due the next business day — Monday, November 2 in our Net 60 example. But some agreements require payment by the stated date, meaning the money must arrive on the last business day before the weekend. Nothing in "Net 60" itself decides this; only the contract or the supplier's stated terms do. When it matters, check the wording or simply ask — and when in doubt, paying a day early is never wrong.

(This article describes common payment-term conventions, not legal or accounting advice — for contracts or disputed invoices, the written agreement and a qualified professional are the authorities.)

If you're unsure whether your terms count calendar or working days in the first place, our guide to calendar days vs business days covers how to tell — but for net terms specifically, calendar days is the overwhelming standard.

The Discount Variant: 2/10 Net 30

Invoices sometimes read "2/10, Net 30." Translation: take a 2% discount if you pay within 10 days; otherwise the full amount is due in 30. That small percentage is larger than it looks — a 2% saving for paying 20 days early is, annualized, a return most businesses can't beat anywhere else. If cash flow allows, early-payment discounts are usually worth taking.

The date math is the same twice over: invoice date + 10 days for the discount deadline, invoice date + 30 for the final due date.

Tracking Overdue Invoices

The same math runs in reverse when you're the one waiting to get paid. An invoice's age is just the days between its date and today — our Days Between Dates calculator gives you that in one step, and comparing it against the net period tells you exactly how overdue a payment is. Many businesses escalate reminders at 30, 60, and 90 days past due, so a quick day-count is often the first step of collections.

And if your own workflow runs on working days — say, following up five business days after a due date passes — the Work Days Calculator counts those, skipping weekends and — with its toggle on — US federal or custom holidays.

Related Calculators

• Date Add/Subtract Calculator — add the net period to any invoice date to find the due date
• Days Between Dates — count an invoice's age or days overdue
• Work Days Calculator — count working days for follow-up schedules, with optional holiday exclusions

FAQ

Does Net 30 mean calendar days or business days? Calendar days, almost universally — weekends and holidays count. Net 30 is about one month of real time, not six weeks of working days. A contract can define it differently, but that's the rare exception.

Does the clock start from the invoice date or when I receive the invoice? The standard is the invoice date. Some agreements specify "from receipt of invoice" or "from delivery of goods" instead, so if the invoice arrived long after its printed date, check which rule your contract uses.

What does 2/10 Net 30 mean? Pay within 10 days and take 2% off; otherwise pay the full amount within 30. The first number is the discount percentage, the second is the discount window in days.

What happens if the due date lands on a weekend or holiday? Most commonly, payment is due the next business day — but conventions vary, and some terms require payment before the weekend. The contract wording decides; when it's silent, ask the supplier.

Is Net 30 the same as "due in one month"? Close, but not identical. Net 30 is exactly 30 days, while months run 28 to 31 days. An invoice dated January 31 on Net 30 terms is due March 2 (in a non-leap year) — not "the end of February."