How to allow per-user outbound gateways in G Suite

Step by step instructions for changing G Suite settings to allow per-user outbound gateways

This is the current solution for allowing the per-user gateway in G Suite so that the “Send As” another email address feature in Gmail can be enabled, when this error message appears:

You must send through (my domain) SMTP servers when you send as (my email address). However, this functionality is not available for your account. Please contact your domain administrator for more information.

From a desktop computer:

Step 1: Log in to the G Suite account for your domain name

Go to
Login with your domain’s administrator credentials

Login G Suite Admin Dashboard

Step 2: Select Apps

G Suite Apps dashboard selection

Step 3: Select G Suite

G Suite app settings dashboard

Step 4: Select Settings for Gmail

Gmail settings inside G Suite dashboard

Step 5: Select End User Access

Gmail End User Access settings

Step 6: Scroll to find “Allow per-user outbound gateways” select it to edit

Outbound gateway settings for Gmail

Step 7: Check the box for “Allow users to send mail through an external SMTP server when configuring a “from” address hosted outside your email domain” to ON

Gmail per user outbound gateways settings

Step 8: Select “Save”

Important to note is that Google says it can take up to an hour for the change to propagate to all users.

The reason you would want to allow per-user outbound gateways in G Suite is so that you can add another email address to your existing Gmail account.

Add another email address to Gmail

Following the steps above are a prerequisite for being able to add another email address to your current Gmail account. Meaning, if you own another email address, you can send mail as that address from your current Gmail account.

Sending emails from a different address, or “alias,” includes being able to send from these kinds of email addresses:

  • Outlook, Yahoo or other non-Gmail address
  • Custom domain name: Your work, school, or business domain like
  • Another Gmail address

For the full set of instructions on how to add another email address to Gmail, visit the Google support page: