How severe is a SORBS listing impact on email delivery?

Marketer from Email Geeks shares that if you're B2C they wouldn't expect it to be significant and it's fairly easy to delist from.

Email marketer from EmailOnAcid Blog says that SORBS listing may affect some recipients but its impact has diminished. Being listed on other major blacklists, however, is more critical.

Email marketer from MXToolbox Knowledge Base explains that while SORBS was once a significant blacklist, its impact has decreased. However, being listed can still cause issues with smaller ISPs or those using older spam filters.

Email marketer from Senderscore shares that a SORBS listing impacts your sender reputation and can affect email deliverability to recipients using services that utilize the SORBS blacklist.

Marketer from Email Geeks explains it depends on your market, they know of two major web hosting companies in Denmark which use SORBS in their Spamassassin configuration. If you’re in that market a SORBS listing could result in ~20% of recipients not receiving e-mails from you.

Email marketer from SparkPost Blog shares that SORBS is less influential now but a listing may indicate other underlying deliverability issues.

Email marketer from StackOverflow shares that if a receiving mail server uses the SORBS blacklist, emails from a listed IP will likely be rejected or marked as spam.

Marketer from Email Geeks shares they’ve seen SORBS listings be quoted back in reasons for blocks at Proofpoint (very rarely though)

Email marketer from Mailjet explains a SORBS listing can cause emails to be blocked or sent to spam by email providers and servers that use SORBS as a reference for spam detection, though it may not always result in a significant impact.

Marketer from Email Geeks states that to their knowledge a SORBS listing never had any noticeable impact on delivery.

Email marketer from Validity (formerly Return Path) details that a SORBS listing can have a variable impact on deliverability, primarily affecting deliverability to systems that still actively use the blacklist, and its significance can depend on the type of SORBS list and the recipient's email provider's filtering policies.

Email marketer from Email Deliverability Forum says that a SORBS listing's impact depends on the recipient's email provider. Some providers heavily rely on it, while others ignore it.

Marketer from Email Geeks states there is no impact.

Email marketer from Reddit says that a SORBS listing generally doesn't have a major impact on deliverability but it can lead to a message ending up in the junk folder.

Expert from Word to the Wise explains that in 2023, SORBS is less important than it used to be, but a listing can still impact deliverability, especially for smaller email providers or older systems that rely on it. The severity depends on the specific SORBS list you are on.

Expert from Word to the Wise shares that SORBS has a few different types of listings, some are bad data and can be removed very easily, some are dynamic IPs that should not send email anyway.

Expert from Email Geeks shares that Proofpoint own SORBS, and do share a subset of the feeds but have wildly different policies, though.

Expert from Email Geeks shares that there is no impact but if you’re listed on the meaningful SORBS lists in 2020 it’s somewhat likely you’re doing something bad that will impact your delivery elsewhere, it is correlation rather than causation so you won’t see that impact change before/after the SORBS listing.

Documentation from BarracudaCentral indicates that they may use SORBS data as part of their spam filtering but a SORBS listing alone is not definitive for blocking email.

Documentation from Cisco Talos shares a SORBS listing can affect deliverability as Talos may incorporate the data to identify potentially malicious or spam-related email sources.

Documentation from Spamhaus Project explains that SORBS is now maintained by Proofpoint, and the impact depends on the specific list you are on. Some lists are more heavily weighted than others.

Documentation from Proofpoint indicates that SORBS (now owned by Proofpoint) impacts email deliverability depending on the configuration of the receiving mail server and the specific SORBS list. Some organizations rely on it more than others.

Documentation from MultiRBL states that while they aggregate multiple RBLs, the impact of a specific SORBS listing will vary depending on how heavily each individual RBL is weighted by receiving mail servers.