How does Spamhaus decide whether to list a subdomain or a whole domain on the DBL?

Email marketer from Email Marketing Tips Blog responds Spamhaus will consider the type of spam being sent. If the spam is particularly harmful (e.g., phishing, malware distribution), the entire domain is more likely to be listed as a preventative measure, regardless of whether only a subdomain is directly involved.

Email marketer from Deliverability.com shares that the volume of spam originating from a subdomain is a factor. A high volume of spam from a single subdomain is more likely to trigger a listing of the entire domain, especially if it suggests a systemic issue or compromise.

Email marketer from Stack Overflow explains that Spamhaus often lists subdomains rather than entire domains when only the subdomain is responsible for sending spam. This approach allows legitimate services using the main domain to continue operating without interruption, while still blocking the specific source of the spam.

Marketer from Email Geeks explains that when it comes to the DBL it depends on what kind of listing that you have if it will be a subdomain only or both. If we see the domain as compromised yet legit and a subdomain is exhibiting the compromise that is what will be listed. If it is something that we have not determined that is a legit website we will list both the subdomain and the domain.

Email marketer from EmailGeeks forum shares Spamhaus considers how responsive the domain owner is to addressing the spam issue. If the owner promptly investigates and resolves the problem, Spamhaus is more likely to list only the offending subdomain. Lack of response can lead to the entire domain being listed.

Email marketer from Email Marketing Forum explains that Spamhaus also considers the reputation of the domain. Newer domains with little history are more likely to be entirely listed if they exhibit spam-like behavior, whereas established domains with a good reputation might only have their subdomains listed initially.

Email marketer from Reddit shares that Spamhaus may list an entire domain if it appears that the domain owner is not taking steps to prevent or address spam originating from their domain. If they are responsive and working to resolve the issue, Spamhaus is more likely to list only the specific subdomains involved.

Email marketer from Mailgun Community Forum responds that Spamhaus' decision can depend on whether the subdomain has its own established reputation, independent of the main domain. A subdomain with a poor history of sending practices is more likely to be listed, even if the main domain has a good reputation.

Email marketer from Affiliate Marketing Forum shares that Spamhaus is more likely to list the whole domain if it's associated with unethical or illegal affiliate marketing practices. In such cases, the domain is considered to be inherently involved in spam activities.

Expert from Email Geeks explains you do not get listed on Spamhaus for a single spam trap, however you *may* (in some circumstances) get listed on Spamhaus for spamming a single, real person. Spamhaus are actual people and they have email addresses. They also state that complaints don’t correlate with spamhaus listings and they've had clients with horrifically high complaint rates and no listings and low complaint rates with listings.

Expert from Spam Resource explains that Spamhaus's listing criteria depends on the type of abuse. If the abuse is specific to a subdomain, like a compromised web form sending spam, only the subdomain is likely to be listed. However, if the entire domain is set up for the purpose of sending spam or hosting phishing sites, the whole domain will be listed.

Expert from Word to the Wise explains that listing only the subdomain is preferable for large ESP's that support many customers. They want to block bad actors and spammers without blocking a whole ESP. If one customer uses a subdomain to send spam, Spamhaus may choose to block that subdomain only instead of blocking the ESP's root domain.

Expert from Email Geeks explains that Spamhaus recently made a change to the DBL where they list only the subdomain, but it is not an always/never situation. If they’ve seen spam with multiple subdomains, they may just list the whole domain. Also, the change was primarily made so they could selectively list ESP click and image links, rather than blocking the whole ESP. If it’s a single company there’s no reason to be selective in the listings.

Documentation from Talosintelligence.com shares that delisting policies will also come into play. Even if a whole domain is initially listed, prompt action and adherence to Spamhaus’ delisting requirements can lead to the listing being reduced to just the offending subdomains.

Documentation from URIBL.com shares the listing of a subdomain or domain on a DNSBL like Spamhaus’ DBL depends on several factors, including the severity and pervasiveness of the spam activity. A single instance of spam might not trigger a listing, but repeated offenses or widespread spam campaigns originating from a particular domain or subdomain will likely result in a listing.

Documentation from MultiRBL.valli.org explains that historical data also plays a role. If a domain has a history of previous spam-related incidents, Spamhaus might be more inclined to list the entire domain, even if the current issue is limited to a subdomain.

Documentation from Spamhaus.org explains that the DBL (Domain Block List) lists domain names which are proven to be involved in spam or other malicious activities. Spamhaus may list a whole domain or a subdomain depending on the severity and scope of the spam activity. If the entire domain is dedicated to spam, it's more likely to be listed, whereas if only a subdomain is compromised, only the subdomain might be listed to limit the impact on legitimate users of the domain.

Documentation from Proofpoint.com explains that the decision to list a subdomain or a whole domain is often based on a reputation analysis. If the main domain has a strong, positive reputation, Spamhaus might only list the offending subdomain. However, if the overall domain reputation is poor or questionable, the entire domain might be listed.