Outbound mail sent from any source can be routed through UltraSMTP using UltraSMTP's Passthrough Service. This includes messages sent from other outgoing SMTP services (such as ISP-hosted SMTP servers), mail sent from webmail services (such as Yahoo Mail, Hotmail, and Gmail), and email messages sent by web applications.

To route a message through UltraSMTP's Passthrough Service, simply append .ultrasmtp.com to the recipient's email address. For example, to send a message to joesmith@aol.com through UltraSMTP's Passthrough Service, you would address the message to joesmith@aol.com.ultrasmtp.com.

Note: Messages must be sent FROM the registered email address on your UltraSMTP account.

UltraSMTP will remove the .ultrasmtp.com suffix from the recipient's email address, apply any tracking and delivery confirmation features enabled on your account, and deliver the message.