About Recurring Invoices
If you send the same invoice to a client periodically, then you can set up a recurring invoice. For example, consider you are a service provider who sends invoices to clients every month. Instead of manually creating the invoice every month, you can set up a recurring invoice. When it is time to send the invoice, a click of a button will do the job.
If you have set up recurring invoices that are waiting to be sent, you will see a number next to Recurring in the source list of the Billings window. This number shows how many invoices are waiting to be sent.
If you want to know the date when the last invoice was sent, then double-click the recurring invoice edit card to open it and view this information.