Salesforce 'Email Relay' with Gmail

Step 1: Configure Gmail SMTP Relay in Google Workspace (G Suite)

A Gmail (Google Workspace) administrator must set up Gmail SMTP relay to allow Salesforce to route outgoing email through Google. To configure this:

1. Sign in to the Google Admin Console.
2. Navigate to Apps > Google Workspace > Gmail > Routing.
3. In the SMTP relay service section, click Add Another Rule (or Configure).
4. Set the Allowed senders to "Only addresses in my domains" or "Any addresses" depending on your requirements.
5. Enable Require SMTP Authentication if you want username/password authentication (recommended).
6. Enable Require TLS encryption for secure transmission.
7. Optionally, restrict to specific Salesforce IP ranges. For the full list of Salesforce IP addresses to allowlist in G Suite, see Ensure you can receive email from the Salesforce application.
8. Save the configuration.

For detailed Google documentation on both relay methods, see the Google SMTP relay setup guide. Two methods are available — test both and apply the one that meets your requirements.

Step 2: Configure Salesforce Email Relay

Once the Google Workspace setup is complete, the Salesforce administrator must configure the Salesforce side:

1. In Salesforce, navigate to Setup > Email > Email Relay Activation (or search "Email Relay" in Quick Find).
2. Click Create New Email Relay.
3. Enter the following Gmail SMTP relay settings:
   1. Host: smtp-relay.gmail.com
   2. Port: 587 (TLS) or 465 (SSL)
   3. TLS Setting: Required
4. If SMTP authentication is required, enable SMTP Authentication and enter the Gmail account username and application password (not the regular Google account password — generate an app password in your Google account security settings).
5. Save the settings and activate the relay.

For full Salesforce email relay configuration steps, see Set Up Email Relay in Salesforce Help (includes the option to enable SMTP authentication).

Verification

After setup, send a test email from a Salesforce Case or through the Lightning Email Composer. Verify in Gmail Workspace logs that the email was routed through the SMTP relay.