As of now, PDF is the only file format that CORE supports for sending invoices. However, you can export invoices in the CSV format from the Invoices screen (More menu) or in the Word, Excel, CSV, etc. format from the Preview window. If you would like to send an idea for a new feature or improvement, submit it to our team at CORE-Ideas@bqe.com or post it on CORE Community under Feature Requests.