Passive Spam Block List (PSBL)


The Passive Spam Block List (PSBL) lists IP addresses that are unknown mail servers, when they send email to a spam trap and the message cannot be identified as non-spam.

  • Listings occur at the IP level.
  • The impact on deliverability is high.

Reasons for getting listed

IP addresses are listed for:

  • Sending spam email to a spam trap from an IP address that is an unknown mail server

How to get off this blacklist

Removal is easy; just request removal using the form on the PSBL website. Listings also expire automatically after a few weeks if your IP address stops sending email to PSBL spam traps.

Identify and fix the cause of the listing prior to requesting removal to help ensure the listing does not recur. Additional details about the listing may be requested by emailing

Tips for staying off this list

  • Send a confirmation email to new subscribers to make sure they want to get your email
  • Follow list hygiene best practices
  • Use a suppression strategy for unengaged users
  • Take recipients who unsubscribe off your list promptly
  • Apply for whitelisting at
    • PSBL uses this whitelist to exclude known, good email servers from being listed. The trust level of your server must be low, medium or high to be considered for exclusion.
  • Consistently run security scans to check your email and non-email servers for viruses and malware using your system to send spam


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