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What ports do I use for outbound email?
We only support secure, authenticated outbound SMTP. Use the table below to find the right port for your mail client.
We only support secure, authenticated outbound SMTP. Use the table below to find the right port for your mail client.
Authentication is required on all outbound SMTP connections. Make sure your mail client is configured to log in with your full email address and password when sending.
Port options at a glance
| Port | Encryption | SSL/TLS required? | Notes |
|---|---|---|---|
| 587 | STARTTLS | Yes | Recommended for most mail clients |
| 465 | SSL/TLS | Yes | Use the secure hostname to avoid certificate warnings |
SMTP with STARTTLS (port 587)
Port 587 uses STARTTLS to upgrade the connection to an encrypted one. In your mail client, set the outbound security to STARTTLS (sometimes labelled "STARTTLS" or "TLS") and make sure authentication is enabled.
Many ISPs block outbound connections on port 25 to limit spam from virus-infected computers. Port 587 is the standard authenticated submission port and is less likely to be blocked. See this article for more detail.
Encrypted SMTP (port 465)
Port 465 uses SSL/TLS encryption. To use it, tick the "requires SSL" option in your mail client's outbound server settings, and make sure authentication is enabled.
You can use mail.yourdomain.ext as the outgoing hostname, but your mail client may warn you that the SSL certificate is untrusted. To avoid that warning, use the server's shared SSL hostname instead - this takes the form servername.secure.kualo.net (or servername.secure.kgix.net for reseller accounts). Both addresses connect to the same server; the shared hostname is simply the one the SSL certificate is issued to.
If you are not sure which hostname to use, you can find the correct server details in cPanel - see Finding the email client configuration details in cPanel for the accurate settings for your account. Alternatively, raise a support ticket and the team will confirm the correct address.