Net 30 Due Date Checker — Quick Invoice Due Date Calculator (2026)

How This Checker Works

This tool answers the single most common invoice question: "if my invoice is dated X, when is it due under Net 30?" It adds your chosen term (15/30/45/60/90 days) directly to your invoice date and returns the exact calendar due date — no spreadsheet, no manual counting.

Calculation: deterministic date arithmetic — no AI, no estimation

Formula

due_date = invoice_date + term_days
term_days ∈ {15, 30, 45, 60, 90}

Uses calendar days from the invoice date, the most common default. If your agreement uses delivery date, end-of-month, or business-day counting instead, see the full calculator linked below.

Net 30 Quick Reference

Term	Days added	Typical use
Net 15	15	Short-cycle vendors, tighter cash flow needs
Net 30	30	Most common B2B default
Net 45	45	Mid-size contracts, moderate buyer leverage
Net 60	60	Larger enterprise/vendor agreements
Net 90	90	Extended terms, strong buyer negotiating position

Need More Than a Single Due Date?

This checker handles the one-off question fast — invoice date in, due date out. But real invoicing work usually needs more: which start date actually applies (invoice date, delivery date, or end-of-month), whether your contract counts calendar or business days, and what an early-payment discount is worth if your vendor offers one. That's exactly the gap PaymentTermsCalculator.com fills — a free, full-featured Net 30/60/90 calculator built specifically around the ambiguity most calculators ignore.

Concrete ways people use the full calculator beyond a single due date:

Contract start-date disputes: pick invoice date, delivery date, or end-of-month (EOM 30) basis to see how each one changes your actual due date — useful when a vendor and buyer disagree on when the clock started.
Business-day contracts: toggle to business-day counting when your PO explicitly excludes weekends, instead of manually skipping Saturdays and Sundays.
Early payment discounts: model a 2/10 Net 30 arrangement — enter your invoice amount and see the exact discount deadline and dollar savings if you pay early.
Comparing payment terms before negotiating: run Net 30 vs Net 60 vs Net 90 side by side to see the real cash-flow difference before agreeing to a vendor's proposed terms.
Accounts receivable review: use the site's DSO (Days Sales Outstanding) calculator to check whether your actual collection times are drifting past your stated terms.

The full calculator covers Net 15/30/45/60/90, an invoice-due-date tool for any custom term, a Net 60-specific calculator, and a DSO calculator — all free, no signup.

Open the Full Payment Terms Calculator →

Frequently Asked Questions

How do I calculate a Net 30 due date?

Add 30 calendar days to your invoice date. Enter your invoice date above and pick Net 30 for the exact due date.

What does Net 30 mean?

Net 30 means the full invoice amount is due 30 days after the invoice date (or delivery date/end of month, depending on the agreement).

Is Net 30 calendar days or business days?

Net 30 defaults to calendar days unless your contract specifies business days.

What is the difference between Net 30 and Net 60?

Net 60 gives the buyer twice the payment window of Net 30 — 60 days instead of 30 from the start date.

Does this checker handle Net 15, 45, 60, and 90 too?

Yes — pick any of the standard Net terms from the dropdown to get your due date.

What if my invoice due date falls on a weekend?

Most Net terms use calendar days, so the due date can land on a weekend — payment is typically still expected by the next business day. Confirm with your vendor if unsure.