Note: From the main Invoices list, you must also filter the Group By to either Invoice Totals or Invoice Details.

Tick Display Notes to display the Notes panel at the bottom of the screen.

Select an invoice/invoices and click Add Note to Selected Invoices to add notes to single or multiple invoices or select a single invoice and click New from the Notes section at the bottom of the screen to add a note to a single invoice

OR

Select an invoice with an existing note

and add a Follow-up Date.

Open an invoice.

From the Notes tab, select the note and enter a date in the Follow-up Date.

Upon adding Follow-up Dates, a reminder is added to the To Do list and the Reminder queue.