Are the days calendar or business days?

Calendar days, as in this tool and in Knock. If your contract says business days, count those separately.

When does the term start?

Usually from the invoice date. Some contracts count from receipt or from delivery, so check what you agreed with the customer.

How does Knock use payment terms?

Each subscription has payment terms, and the due date of every invoice generated for it is the period start plus the term.

Free tool

Payment terms due date calculator

Find the due date for immediate, Net 15, Net 30 and Net 60 terms.

Invoice date

Payment terms

Payment received on (optional)

Due date

Wed, 19 Feb, 2025

ImmediateMon, 20 Jan, 2025

Net 15Tue, 4 Feb, 2025

Net 30Wed, 19 Feb, 2025

Net 60Fri, 21 Mar, 2025

What it calculates

Payment terms say how long a customer has to pay. Net 30 means payment is due 30 calendar days after the invoice date. Immediate means due on receipt.

The formula

Due date = invoice date + term days
Terms: immediate 0, Net 15 = 15, Net 30 = 30, Net 60 = 60 calendar days
Days overdue = payment date - due date, if positive

Worked example

Invoice dated 20 January 2025

Immediate: 20 Jan 2025
Net 15: 4 Feb 2025
Net 30: 19 Feb 2025
Net 60: 21 Mar 2025

Questions

Stop doing this by hand

Knock runs these numbers for you: recurring invoices, GST per line, payment terms and live revenue reports.

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