With Nextiva, you can send unlimited faxes to any fax number in the United States, Canada, or Puerto Rico without a fax machine. In short, Faxing over VoIP ('FoIP') works regardless of the recipient's phone number. You can send faxes regardless of whether the recipient uses digital or analog phone lines. Your outbound faxes must meet certain basic requirements for recipients to receive your entire message. You can send up to 10 attachments and 5 MB per fax message. Nextiva’s internet fax service does not currently support international faxing.