Knowledge Base

Using external SMTP servers to send e-mail

You may want to use an external SMTP server (such as those provided by Google or Mandrill) to send e-mail messages from your A2 Hosting account.

However, if you have one of the following hosting packages, you cannot use external SMTP servers to send e-mail:

  • Web hosting (Lite, Swift, or Turbo)
  • Reseller hosting

For these hosting packages, you must use A2 Hosting servers to send e-mail messages. A2 Hosting enforces this restriction to help prevent outgoing spam from our servers. It only takes one user sending spam from a shared server to negatively impact e-mail for all of that server's users.

Use of an HTTP API using standard ports is not limited for Web Hosting and Reseller accounts. Ask your mail provider if they offer an API to use instead of SMTP. HTTP API mail sending plugins are available for popular CMSs from companies such as Sendgrid, Mailgun, Mandrill and Elastic Email. HTTP APIs can also be used in custom programs as in this example.

All other hosting packages are not subject to this restriction, so you can freely send e-mail messages through external SMTP servers. These hosting packages include:

  • Managed VPS
  • Managed Flex Dedicated Server
  • All unmanaged hosting packages