The Spamhaus Project


How to manage email complaints

Monitoring email complaints is a vital piece of the reputational “pie," so keeping them as low as possible should be every marketer's goal.

by The Spamhaus TeamFebruary 15, 20224 minutes reading time

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Monitoring email complaints is a vital piece of the reputational “pie,” so keeping them as low as possible should be every marketer’s goal. There are many reasons recipients click “report spam,” some of which are manageable, and some are not.

Manageable email complaints

  • They didn’t sign up to receive the email you’re sending to them. Don’t send emails to people unless you have, at a minimum, opt-in from them.
  • Failure to correctly set recipient expectations regarding frequency and content. Be clear in your confirmation opt-in email of what your recipients can expect to receive and how often they will receive it.
  • They get too much email from you, or there has been a notable change in frequency. Mail that is too frequent can annoy recipients. Conversely, mail that is too infrequent may be unexpected, and recipients will report the mail as spam. Be consistent.
  • The mailing list was purchased. Management of this issue is simple – don’t purchase lists!
  • The messages your recipients are receiving aren’t relevant. Content that your recipients don’t like can frustrate them to the point that they report it is as spam. Targeting the correct demographic and audience is crucial.
  • Sending mail after the recipient has unsubscribed. A recipient should be removed from your mailing list immediately if they unsubscribe, regardless of how long the applicable law says it is permissible to wait.

Less manageable email complaints

  • Recipients don’t remember signing up. You can’t control someone’s memory; however, if they unsubscribe, ensure you action this immediately. You can control frequency; if someone signs up and you don’t send the first email for weeks or months later, they will forget.
  • The address was collected at the point of sale, and human error took over. Once again – this is out of your control. Just ensure that anyone who unsubscribes never receives another unsolicited email from you because you can guarantee that they will report it as spam next time.
  • Frustrated recipients reporting indiscriminately. Some recipients get so annoyed with the amount of email they receive that they will select large portions of their email box and report all of it as spam.

Tools to help with email complaint management

Some ISPs offer more in-depth data about what happens to email once they have accepted it. Here’s a selection:

  • Hotmail Smart Network Data Service – SNDS-provides data about traffic such as mail volume, instances of deferrals or tempfails, complaint rates, and the number of their traps hit.
  • GooglePostmaster Tools – provides limited data about complaint volumes and domain reputation via a web interface.
  • Participate in all available feedback loops (see below for more details)
  • Contract with a reputable Deliverability Consultant or hire a reputable email analytics company. Not all are created equal, so you should research these carefully.

Email feedback loops

A “feedback loop” (FBL) allows Internet Service Providers (ISPs) to report spam complaints submitted by their users to the originating network. This is done using Abuse Reporting Format (ARF), a machine-readable format that redacts personally identifiable information. Some major ISPs offer a feedback loop as a free service.

You should process these reports promptly and immediately remove the complainants upon receipt. The length of time allowed for suppression to occur varies by law and country, so ‘immediately’ is the best practice.

The number of complaints generated by a given IP is given significant weight by receivers, though ISPs will not reveal the threshold as it is part of their spam filtering recipe and will vary from ISP to ISP. A good reputation allows slightly more forgiveness than a poor one. That being the case, keeping complaints as low as possible is the prudent thing to do.

Advice to help marketers avoid email complaints

  • When you confirm an opt-in, be clear about what the user will receive and when. Keep that promise.
  • Offer different frequency options that recipients can manage via a preference center.
  • Don’t pre-check subscription boxes.
  • Make unsubscribing super easy. Some laws regarding marketing mail require this, but even if they don’t, it’s always better to have someone use an unsubscribe link than report spam.
    • Do not require a log-in to unsubscribe. It is illegal in some places and makes subscribers angry everywhere.
    • Place the unsubscribe so it can be easily found, for example, a link on the top of the email. If receivers can’t locate it quickly, they will report it as spam instead.
  • Use careful segmentation and A/B testing to ensure that you send email to the most well-targeted and engaged audience possible.

If you sign up recipients via confirmed opt-in, keep your mailing lists clean, and only send relevant content to engaged contacts, you should have minimal complaints to manage. But, if you do receive them, we urge you to deal with them rapidly. Next in our guide is a detailed look at spamtraps.