5 Ways to Prevent Blacklistings — the Genius Approach

“Intellectuals solve problems; geniuses prevent them.” When Albert Einstein relayed this very wise message, he was decades removed from a world of computers and email marketing. However, Return Path email geniuses still follow this simple principle, helping clients prepare for problems before they occur. Blacklisting can be a major roadblock to inbox placement, so Return Path recently published an ultimate guide to blacklists to share research on blacklisting trends. The following highlights can help you channel Einstein and prevent blacklistings before they’re a problem.

1. Use a dedicated IP address:
Shared IP addresses can attract blacklistings for a number of reasons. Other senders on your shared IP might be exhibiting “spammy” behavior resulting in blacklistings that have nothing to do with your own sending practices. Moreover, the high quantity of mail sent on a shared IP might trigger blacklistings. It is a best practice to utilize a dedicated IP address so that your reputation and deliverability are not impacted by other senders.

2. Avoid “spammy” behavior:
While blacklist operators are more concerned with the permission you have/may not have to send to receiving addresses, “spammy” content can play a role in blocking. This webinar uncovers list domains and hyperlinks which blacklists may associate with spam. Moreover, high quantities of mail and suspect sending frequencies may lead to a blacklisting.

3. Be aware of weekly trends:
As illustrated in the blacklist infographic, Friday was a common peak day for popular blacklists. CBL/XBL and pbl.spamhaus.org all shared Friday as a top blacklisting day, generating 29% and 22% of weekly blacklistings respectively on Friday. SpamCop peaked at only 18% on Thursday. Dnsbl.ahbl.org (now retired) saw a substantial 71% on Sunday, while sbl.spamhaus.org performed 68% of their blacklistings on Wednesday.  With the exception of dnsbl.ahbl.org, which is no longer in operation, the day of the week with the least blacklisting events fell on either Sunday or Monday for all analyzed blacklists.

4.Consider seasonal trends:
Blacklisting rates increase dramatically during the holiday season with more than 49% of blacklistings taking place in November and December. This may occur because email marketers take on more aggressive (and spam-like) tactics to attract consumers during the important holiday season. It is crucial to maintain your reputation and uphold best practices to avoid blacklists during this popular sending time. Summer months produce the second highest volume of commercial email as well as the second highest blacklisting rate. 

5. Know the prime offenders:
While Gmail does not publicly disclose which blacklists they use, our data shows a correlation in Gmail blocking and being listed on pbl.spamhaus.org (PBL), sbl.spamhaus.org, the CBL/XBL. Placement on the PBL led to a 58% average decline in Gmail Inbox Placement Rate. If you are struggling with inbox placement at Gmail, check for placement on these blacklists. While the listing itself may not be cause of the delivery issues, it does indicate list hygiene or infrastructure issues.

With these five tools, you are on your way to blacklist-free bliss. However, even Einstein didn’t work alone, and Return Path can help you prevent and address blacklistings. Return Path’s Blacklist Alert provides critical automated alerting when one of your IPs appears on a blacklist. You’ll also receive insight regarding the blacklisting reason and how to remove the listing before it significantly affects your deliverability. Moreover, Return Path can serve as an intermediary when dealing with stubborn blacklist operators, who sometimes impose unfeasibly high standards before considering de-listing. Great things happen when geniuses work together, and we look forward to assisting you in your crusade against the blacklist. 

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