What does net 30 mean on an invoice?

Net 30 means the customer has 30 days to pay the full amount of the invoice. "Net" is the total after any agreed discounts or credits, and 30 is the number of calendar days they have. An invoice dated 1 March on net 30 terms is due on 31 March.

When the 30 days start

Usually from the invoice date. Some contracts count from the date the invoice is received, or from the end of the month it was issued, which is often written "net 30 EOM". If your terms do not say, customers will tend to pick whichever reading pays you later. The fix is to print the actual due date on the invoice, not only the terms.

Other terms you will see

• Net 15, net 45, net 60: the same idea with a different number of days.
• Due on receipt: payment is expected as soon as the invoice arrives. In practice many customers treat it as "soon", so a date still helps.
• 2/10 net 30: the customer may take 2% off if they pay within 10 days; otherwise the full amount is due in 30.
• Net 30 EOM: 30 days after the end of the month the invoice was issued in, so a 5 March invoice is due 30 April.

How to write net 30 on an invoice

Payment terms: net 30. Due date: 31 March 2026.

Put both. The terms tell them the arrangement; the date removes any argument about how to count. If you charge late fees, say so on the invoice too, and check what your local law allows before you do.

What to do when net 30 passes

A day or two late usually means the invoice is sitting in an approval queue or waiting for a payment run. Send a short, friendly note on day one, and ask when it is scheduled to be paid. The aim at this stage is a date, not a stronger tone.