Fax SMTP – Basic Usage

This section explains the basic usage of our fax SMTP gateway for automatic faxing.

The minimal requirement for initiating a fax is sending an email with the following parameters. The resulting fax will be a plain-text document whose content is the email body.

Field Format Comments
From Email Address

This address is used for authentication. Therefore, it must be an “allowed sender” address in an InterFAX account.This address will also be used as your fax identifier (CSID), i.e. this is what the recipient will see on the LCD screen of his fax machine.

PHP Developers note: When sending an email to fax from PHP it is not enough to set the “From:” address in PHP’s mail() command. You MUST set the sendmail_from address in PHP.INI to be the same as an allowed sender in your Interfax account (see https://www.sitepoint.com/article/679).

To faxnumber@fax.tc E.g., +12125558596@fax.tc. See How to format fax numbers in Interfax .
Subject String, max 60 characters This string may be used for your reference and will appear in the reply email and in the web-based admin screen.
Body String This is the body of the fax. Text may be any length. Format may be plain text or HTML – if both are present, HTML will be faxed.

Optional Fields

Field Format Comments
CC Email Address Interfax will accept addresses entered into this field.
BCC Email Address Interfax will accept addresses entered into this field.
Reply-To Email Address Confirmations will be sent to this address (Default is to use the “From:” address).