Billings Pro allows you to export your financial data from Billings Pro into QuickBooks. This requires you to have QuickBooks 2011/2012/2014 for the Mac. QuickBooks Online and Quickbooks from Mac App Store are not supported.
You can export the following from Billings Pro:
How to map clients from Billings Pro to customers in Quickbooks:
If a client exists in both Billings Pro and Quickbooks, you can map the Billings Pro client to the same customer that exists in Quickbooks. You may also choose to map the client to any other customer of your choice. When no mapping is assigned and data is exported, the client will be sent over as a new customer in Quickbooks.
You don't need to have Quickbooks open and running to be able to export information
Multiple Billings Pro clients can be mapped to the same customer in QuickBooks