You put so much work into your email marketing campaigns. Yet, it can be all for naught if it they never reach the inbox. If this sounds like you, perhaps you’ve been blacklisted.

Blacklists are comprised of IP addresses or domains that are blocked from accessing a specific network. There are numerous blacklists on the Internet. Some literally list every single email marketer alive (and possibly dead)—yet carry little to no weight at all with ISPs. Others should be avoided at all costs, including:

1. Spamhaus

Domains and IP addresses with poor sender reputation are listed publicly here. Content reflecting spam and spam traps are monitored through this blacklist.


More than 200,000 companies use SORBS blacklist. Several ISPs and corporations all over the world use this blacklist as part of their filtering system for their networks. It recognizes undesirable senders through partner spam reports and spam traps.

3. SpamCop

SpamCop works as an email spam reporting service that captures senders involving in distributing unsolicited bulk or commercial email.

Actionable Tips to Avoid Blacklists

  • Follow email design best practices like maintaining proper text-to-image ratio and avoiding use of spam trigger words and shortened URLs in your campaigns.
  • Keep track of email metrics like opens, clicks, bounces, abuse/spam complaints, and spam trap hits.
  • Remove hard bounces and repeated soft bounces from your email list.
  • Assess your list frequently and monitor it through list validation service like Kickbox or Webbula.
  • Regularly check your feedback loops (FBLs).
  • Stay updated on the CAN SPAM Act guidelines and the parameters that spam filters and ISPs take into consideration while evaluating email marketing campaigns.

Need more expert insight into email deliverability and how to build and maintain your sender reputation? Download this eBook we put together with our friends at Inbox Pros.

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