3 Steps to Qualify for Gmail’s “Feedback Loop”

Email marketers are great at tracking positive engagement on their emails in the form of opens, clicks, conversions, and forwards/shares.  But you should be tracking negative engagement in the form of unsubscribes and complaints as well.  Unsubscribes are usually easy to track, since they are generally received and processed through your sending software.  But complaints can be a little harder to track and act on, since the complaints happen within the receiver interface.

So how do you know when subscribers are complaining on your complaint deptemails, and then remove that subscriber from your list so they don’t receive mail from you again?  The answer is feedback loops!

Many receivers, including AOL, Yahoo and Hotmail, offer feedback loops to notify senders when complaints are generated by their users via the "This is Spam/Junk" button.  These ISPs will notify the sender of the complaint via email, and the expectation is that the sender will then remove the complainer from their subscriber list.  This will help to keep your list clean of unhappy subscribers, and in turn will help with deliverability at the participating receivers.

You may have noticed, however, that I left Gmail off the list above.  Gmail unfortunately does not have a traditional feedback loop available to senders.  They do, however, honor the List-Unsubscribe functionality, which we often refer to as Gmail’s “poor man’s feedback loop”.  

The List-Unsubscribe function is text you can include in the header portion of your emails.  When implemented, this will allow Gmail users to register a complaint and unsubscribe at the same time, whereas without the List-Unsubscribe header, users are only given the option to “Report spam” – with no feedback sent back to the sender.  If the Gmail user chooses to “Unsubscribe and report spam”, an email notification will be sent to the sender so they can remove the complaining subscriber from their list.

Gmail Feedback Loop

In addition, if a sender is using the List-Unsubscribe header, their Gmail subscribers will be presented with another option to unsubscribe from the emails without registering a complaint.  This option is found by clicking on the downward-facing arrow underneath the from line of an open message, which then brings up the details box.  This feature is only available if the sender is using the List-Unsubscribe header.

Gmail Feedback Loop

Return Path encourages all email marketers to use the List-Unsubscribe header in their emails so that they can receive this type of negative engagement feedback from Gmail.  There are, however, a few requirements that senders must follow before they can take advantage of the Gmail “feedback loop”:

  1. You must be authenticating your email using SPF (define) or DKIM (define).
  2. You must have a good reputation at Gmail.
  3. You must use the mailto: option within the List-Unsubscribe header.  The email notifications from Gmail would then be sent to this email address.  The List-Unsubscribe mailto: option looks like this in your email header:

From: [email protected]
Subject: Get 20% off – today only!
Date: November 29, 2012 3:13:02 PM EDT
To: [email protected]
List-Unsubscribe: <mailto:[email protected]>

In this case, unsubscribe notifications from Gmail will be sent to me at [email protected]  I'll of course want to ensure this is a valid, monitored email address.


If you are currently experiencing deliverability trouble at Gmail, I highly recommend that you implement the List-Unsubscribe header so you can begin tracking and acting on complaints at Gmail.  This will allow you to have a two-way conversation with Gmail and the Gmail subscribers on your list, and will help to keep the Gmail portion of your list clean.

To learn more about managing complaints, download our "How to Reduce Complaints and Improve Your Reputation" guide.


Photo credit: Life As Art on Flickr

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