The Polspam Wrong Reverse Blacklist (BL) is an IP-based blocklist (or blacklist) from the Polish RBL Polspam that lists IP addresses with misconfigured or incorrect reverse DNS (PTR) records.
The Polspam Wrong Reverse Blacklist (BL), using the zone bl-h5.rbl.polspam.pl, is an IP-based blocklist that lists addresses with incorrect reverse DNS (PTR) records. It is one of several blacklists operated by Polspam, a Polish RBL project dedicated to fighting spam and poor netiquette. This specific blacklist is considered highly restrictive.
The operators of this blocklist advise system administrators to use it with caution, especially lists marked with an "h" in their name. They recommend integrating it with a spam filtering system like SpamAssassin first, rather than using it to reject mail outright. This allows administrators to observe its behavior and adjust scoring before implementing stricter policies. The primary policy is to flag IPs with improper reverse DNS configurations, a common characteristic of servers not configured correctly for sending email, which can include spam sources.
The Polspam project, which operates the Wrong Reverse Blacklist (BL), describes itself as a community-driven, non-commercial hobby. It is a Polish RBL server project that functions based on cooperation with the broader internet community, where volunteers can report spam to a shared database. The organization states that it does not accept donations, is not sponsored, and does not engage in commercial activities. Its sole purpose is to provide information about domains and IPs known for sending spam.
The delisting process for any Polspam blacklist (or blocklist) is stringent and requires complete honesty. They explicitly state they do not delist notorious spammers and only consider removal for one-off incidents that were not malicious in intent. Lying or omitting information will result in your request being ignored.
Before requesting removal, you must fix the underlying issue. For this specific blacklist, that means correcting your server's reverse DNS (PTR) record. When you contact them, you must follow their guidelines precisely:
If you are on a shared IP, you must work with your hosting provider. The provider is responsible for identifying which domain on their server is causing the IP to be on a blacklist. The provider needs to check all hosted domains and remove the spamming ones. After the problematic domains are gone, the IP's reputation can recover.
The impact of being listed on the Polspam Wrong Reverse Blacklist (BL) is generally considered low. Polspam itself clarifies that it does not block any mail directly. Instead, it acts as an informational resource, publishing lists of IPs and domains that it has identified as problematic.
The actual impact on your email deliverability depends entirely on which mailbox providers or system administrators use this specific blacklist. Because it is a more specialized, regional (Polish) blocklist and is described as very restrictive, it is less likely to be used for outright blocking by major global providers. However, recipients whose mail servers do use this list may reject your emails or filter them to the spam folder. The main issue stems from having an incorrect server configuration, which is a negative signal for deliverability regardless of this specific listing.
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
Organization
Zone
Type
Impact
Delisting
19 resources
Besides Spamhaus, what blocklists are important for email marketers to monitor?
Should I use blacklist or blocklist in email marketing?
What are examples of insignificant or ineffective email blocklists?
What common blocklists or services cause 'message rejected as spam' errors for ESPs?
What is the PSBL (Passive Spam Block List) and how does it work?
Why am I seeing Spamhaus DBL block messages for IP address lookups?