Marketing GlossaryBlacklist

Blacklist

June 2025

What is a "blacklist"?

In the context of email marketing, a blacklist is a list of IP addresses or email domains associated with spam.

Once an email domain is blacklisted it will have reduced delivery rates.

By using a reputable email service provider (such as EcoSend) email marketers can avoid being blacklisted. In addition, it's essential to follow good email practices so that emails are not flagged as spam by email servers or recipients, which could also lead to blacklisting.

It is thought that 85% of all emails sent are spam, and blacklisting is one of the ways that email providers look to eliminate the problem to provide a better user experience.

If an email address or domain is blacklisted, it can be challenging to recover from. Therefore, email marketers should be very aware of how to remain both trusted and compliant.

Example

A company that sends unsolicited emails to purchased email lists might find their domain "spammy-company.com" added to major blacklists like Spamhaus. Once blacklisted, emails from this domain will be automatically rejected or sent to spam folders by most email providers, dramatically reducing their delivery rates from 95% to potentially less than 10%.

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