Does an IP blacklist affect DMARC compliance?

No, IP blacklisting does not impact DMARC compliance. DMARC is strictly an authentication protocol, meaning that as long as your security protocols (SPF and DKIM) are properly configured, your emails will pass DMARC checks even if the sending IP address is blacklisted.

However, being on an IP blacklist signals a reputation issue that might sometimes override successful DMARC authentication. Mailbox providers generally refuse to accept mail from known bad actors, so if your IP is blacklisted, they will likely reject the message or route it immediately to the spam folder to protect their users, regardless of the DMARC status.

It is worth noting that blacklistings can sometimes be false positives or related to temporary cache issues, so they are not always permanent or critical failures. If you do find that your sending IP is blacklisted, the next steps depend on your configuration.

If you use a dedicated IP address, you should contact the specific blacklist vendor to request delisting and see what actions should be taken to change your practices so it doesn't happen again. In cases where the blacklisted IP is a shared address (e.g., one of Google’s IP addresses), no action is required or can be taken on your part, as the service provider is responsible for managing their shared IP pools.

In case you have any specific questions, feel free to contact EasyDMARC technical support.