Email Blacklist Check: How to Avoid Getting Emails Blacklisted

To begin with, it’s important to understand how blacklists work. Most blacklists use a so-called “spam trap”, email addresses that are used to identify where the spam mail is coming from, usually an IP address or a domain. If that IP address or domain does not check out, it is blacklisted.

Anyone can set up a blacklist for their own email server, and share the list for the public to use. Not all blacklists are created equal. Smaller blacklists, including SORBS and Spam Cannibal, have less influence with the bigger ISPs. Most large ISPs only use the most reputable blacklists like SpamCop, Spamhaus, and URIBL.

If a server gets on a blacklist such as SpamCop, any email from the server is blocked by ISPs that use the SpamCop blacklist. SpamCop and other reputable blacklists usually have a threshold, and usually, delist servers after a reasonable period of time.

For instance, you can use this blacklist check tool to check if your server is currently listed on any public blacklists.

Despite the fact, that there’s no stop-gap solution, we suggest some best practices help your emails reach inboxes:

Confirm opt-ins: when you send a confirmation email before adding a new recipient to an active mailing list, only valid and engaged recipients will be added to your list. While this practice could potentially decrease the number of marketing email opt-ins for your list, the number of spam reports and unsubscribes will be reduced, which in the long run improves the ROI (return on investment) on each email sent. It also prevents all types of bad email addresses from being added to your list, reducing your hard bounce rates while increasing engagement rates. If you would rather not do double-opt ins, it’s best to have some other verification method (real-time or otherwise) to continuously clean your list.

Validate addresses: checking for validity of the email address and common typos may help reduce friction, caused by confirming opt-ins. What is more, new signups are likely to react positively to this type of feature. There will be a reduction in common domain typos and instances of fake email addresses, resulting in fewer spam trap email addresses getting through to your list and ending up on a blacklist.

Remove unengaged recipients: use a “sunset” policy, which means removing stale recipients based on engagement. You should remove email addresses if that recipient does not open or click a message in a certain period of time, which can vary depending on your industry and send frequency. While your mailing list size will decrease, your ROI per email sent will increase because you will only be communicating with engaged recipients. What is more, you will improve your sending and brand reputation because you don’t need to send emails to people who don’t want them.

Here are some more easy-to-follow but effective suggestions to avoid being blacklisted: