Sending routing setting

The Sending routing setting is one of multiple options on the Email settings page for managing mail routing and delivery. The Sending routing setting enables you to set up outbound and internal-sending delivery options, such as dual delivery and outbound mail gateway.

Users of legacy settings for outbound gateways and outbound blind carbon copy (BCC) messages should avoid similar settings in Delivery Manager to avoid conflicting and unpredictable behavior. These conflicts are currently being addressed. This warning will be removed when they are resolved.

Similar to other email security settings, the Sending routing setting enables you set up policies that vary by organizational unit. Users within child organizational units inherit the settings you create for the parent organization. You also have the option to add multiple Sending routing settings to each organizational unit.

Note: Before you configure Sending routing, you must first add mail routes with the Hosts tab.

Use cases for Sending routing:

  • Set up a smarthost (outbound mail gateway): An outbound mail gateway is a server through which all mail passes that is sent from your domain. The gateway typically processes the mail in some way, such as archiving it or filtering out spam, before delivering the mail. When you use an outbound mail gateway, the Google Apps mail servers pass all outgoing mail from your domain to the gateway server.
  • Route outbound mail to an external archiving server (dual delivery): The Sending routing setting enables you to set up dual delivery by organizational unit for outbound mail traffic. You can set up Sending routing to deliver mail to the intended recipients and to an external archiving server.

For step-by-step instructions on the various use cases, see Managing mail routing and delivery: Guidelines and best practices. For step-by-step instructions on setting up Sending routing, see the sections below.

To configure Sending routing settings for your domain or organizational unit:

  1. Sign in to the Google Admin console.
  2. Click Google Apps > Gmail > Advanced settings.
  3. In the Organizations section, highlight your domain or the organizational unit for which you want to configure settings (see Configure advanced settings for Gmail for more details).
  4. Scroll down to the Sending routing section:
    • If the setting's status is Not configured yet, click Configure (the Add setting dialog box displays).
    • If the setting's status is Locally applied or Inherited, click Edit to edit an existing setting (the Edit setting dialog box displays), or click Add another to add a new setting (the Add setting dialog box displays).
  5. When you're finished making changes, click Add setting or Save to close the dialog box.

    Note: Any settings you add will be highlighted on the Email settings page.
  6. Click Save changes.

In the Sending routing window, click Add a description to enter a unique name for this setting. See the sections below for additional instructions and guidelines.

Email messages to affect
This section enables you to set the policy for outbound and internal mail. By default, the Outbound and Internal - sending boxes are checked. However, for example, to limit this setting to Outbound mail, uncheck the Internal - sending box.
  • Outbound: Messages sent by your users to recipients outside the set of domains associated with your company or organization
  • Internal - sending: Messages sent by your users to recipients within the set of domains associated with your company or organization
For the above types of messages, do the following
For the Sending routing setting, two options are available in the drop-down list: Reject message or Modify message.

Reject message
This option rejects outbound or internal-sending messages sent within the organizational unit and are not delivered to the intended recipient. You can enter customized text for the rejection notice.

Modify message
This option enables you to modify outbound or internal-sending messages by adding headers, changing the route, changing the envelope recipient, adding more recipients (additional, or secondary routes), and removing attachments.

With the Modify message option, you can change the primary delivery, and you can define additional or secondary deliveries that you can use for dual delivery or multiple delivery. See the following descriptions for more details about these controls.

Add X-Gm-Original-To header

By checking this box, a header tag is added in case the recipient is changed so that the downstream server can know the original envelope recipient; for example, X-Gm-Original-To:

Adding the X-Gm-Original-To header is useful if you're rerouting a copy of the message to another recipient. In this case, you're changing the recipient address, but the new recipient wants to know the address of the original envelope recipient. They can see the original envelope recipient by checking the X-Gm-Original-To header in the message.

Add X-Gm-Spam header and X-Gm-Phishy header

Messages that are routed through Gmail are automatically filtered for spam and phishing. Selecting Add X-Gm-Spam header and X-Gm-Phishy header adds the following headers to indicate the spam and phishing status of the message:

For spam

0  indicates that a message is not spam: X-Gm-Spam: 0

1 indicates that a message is spam: X-Gm-Spam: 1

For phishing

0 indicates that a message is not phishing: X-Gm-Phishy: 0

1 indicates that a message is phishing: X-Gm-Phishy: 1

Note: Any message marked as phishy is automatically marked as spam.

Selecting the Add X-Gm-Spam header and X-Gm-Phishy header option enables an administrator at a downstream server to set up rules that handle spam and phishing differently from clean mail.

Add custom headers

You can add one or more custom headers to messages that are affected by a Receiving routing, Sending routing, or other setting. For example, you can add a header that matches the description that you entered for the setting. This can be helpful for analyzing why a message was routed in a certain way, or why a filter was triggered.

Prepend custom subject

You can enter a string to prepend to the subject of messages. For example, if you enter Confidential in this field, message recipients might see the following subject: [Confidential] Monthly report

Change route

This option enables you to change the destination of the message. By default, the Gmail mail server is the primary delivery. However, you can change the delivery; for example, by routing mail to an on-premise mail server, such as Microsoft Exchange.

Before you can change the primary delivery, you must first add mail routes with the Hosts tab. The routes that you add on the Host tab are then visible in the Select a route drop-down list.

Change envelope recipient

To change the envelope recipient, click the options next to the Replace recipient field, and enter the user's email address; for example,

Changing the envelope recipient for a message on the primary delivery is equivalent to forwarding a message to a different recipient. You can also change the envelope recipient on the additional (secondary) delivery, which is equivalent to a "bcc".

Add more recipients

Check the Add more recipients box to set up additional (or secondary) deliveries for dual delivery or multiple delivery.

Select Basic from the drop-down list to add individual email addresses, and then click Save. You can add multiple recipient addresses by clicking Add.

Select Advanced from the drop-down list to choose advanced options for your secondary delivery. Similar to the settings that you modified for the primary delivery, you can change the envelope recipient, add headers, prepend a custom subject, and remove attachments for the secondary deliveries.

Note: Any settings that you configure for the primary delivery also affect the secondary deliveries. For example, if you change the envelope recipient, prepend a custom subject, and add custom headers to the primary delivery, the same configuration is applied to the secondary deliveries.

Remove attachments

Select this option to remove any attachments from messages. Optionally, you can append text to notify recipients that attachments were removed.

For more details and step-by-step instructions about mail routing, including use cases and examples, see Manage mail routing and delivery: Guidelines and best practices.

Execute this setting only if the envelope sender matches
This option is useful to re-route mail for all users in an organizational unit, but only for messages sent from a few different domains. Click the check box, and then enter the list of domains with the following regular expression syntax:


This would cause any message from the above domains to adhere to the route modifications that you you made.

Execute this setting only if the envelope recipient matches
This option is useful, for example, to re-route mail to your Microsoft Exchange server for just four users in a specific organizational unit. Using the Sending routing setting for that organizational unit, you can change the primary delivery to your Exchange server. You can then ensure that this re-route applies only to these four users by entering the list of users with the following regular expression syntax:


For more information, see Guidelines for using regular expressions.

Note: When you're finished, click Add Setting, and then click Save changes to confirm your changes.