A recurring sales invoice is an invoice that is repeatedly sent to the same customer over a specific period of time. This prevents you from manually creating the same invoices for the same contacts every month, quarter, or year. Each of your sales invoices can become recurring so that they will be generated automatically.
Bear in mind that a recurring invoice is not yet an invoice: it is a document that can be converted into an invoice in the time frame that you decide.
When converting a sales invoice into a recurring one, you will have to determine:
It will mark how often the invoices will be issued (Daily, Weekly, Biweekly, Monthly, Bimonthly, Quarterly, Semiannual, Annual)
Date when the first invoice will be issued
Date when the invoice will stop to be issued
If you need your recurring invoices to be created and sent automatically, simply activate the Autocreate & send option.