You will only see the due date on an invoice if the Agreed to pay later checkbox has been selected in the Payments section on the invoice page. If this checkbox is not selected, the due date is not displayed.
The due date delay (in days) can be set in Settings > Clinic location > Clinic location profile > Due date delay. To see the due date on the printed/sent invoice, select Display the due date in the header in Settings > Print settings > Invoice.
How do I see due dates on multiple invoices?
In the invoice list on the Records > Invoices page, you can view due dates in the Due date column. If the column is not visible, select the Columns button and select Due date in the list. You can also use the filters and extended search options to narrow down your search results.