How to set up email retention policy

 To set up email retention:

    Sign in to the Google Admin console.

    From the dashboard, go to Google Apps > Gmail > Advanced settings.

    In the Organizations section near the top of the page, highlight your top-level organization.

    In the Email Retention section, select either Automatically delete email messages older than N days or Do not delete email messages automatically.

    If you select Do not delete email messages automatically, click Save changes and skip the remaining steps.

    Enter the number of days you want to retain messages. For example, if you enter 30, then messages older than 30 days are deleted.

    Specify how to handle automatically deleted messages by choosing one of these options:

        Move messages to the Trash folder: Messages stay in the Trash folder an additional 30 days before they're deleted, which gives you additional time to retrieve a message that was deleted according to your email retention settings.

        Delete messages permanently: Messages bypass the Trash folder and are deleted permanently after the number of days you specify. Once a message is deleted permanently, there is no way to retrieve that message.

    To retain messages with specific labels, enter a comma-separated list of those labels in the text field under Do not automatically delete messages with the following labels.

    You must enter the full names of the labels; wildcard characters are not supported. Nested labels do not inherit this setting from their parent labels.

    You can publish a list of these labels to your users so they have the option to prevent specific messages from being deleted automatically.

    Click Save changes at the bottom of the page.

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