How many faxes can I send at once? XenVoice December 06, 2018 09:39 Updated You can send 5 files at a time. Related articles Can I send faxes to multiple numbers? What are the supported Fax file types and file size? How to send a fax with XenFax? How do I integrate XenVoice with WhatsApp, Slack and Skype? How to create a Fax cover letter?