The new feature appears on promotional emails that arrive regularly, like those from Groupon, your gym or mall stores. Immediately to the right of the sender’s email address, you’ll see a one-touch button to unsubscribe.
When you click Unsubscribe, Gmail sends a request to the sender to remove you from their list. You’ll need to allow a few business days for your name to actually be removed.
Google notes it is unable to provide an Unsubscribe option for all mailing lists. Further, the option to Unsubscribe will not appear on messages sent by known spammers “for your protection.”
Ultimately, the new feature is designed to improve Google’s crowd sourced spam-sorting efforts. Microsoft Outlook implemented a similar feature to improve its spam filters last year.