What to do if your IP is blacklisted on SORBS?

Key findings

• Limited impact: Many experts and marketers report that a SORBS listing typically has minimal direct impact on email delivery to major ISPs.
• Self-resolution: IPs often delist from SORBS automatically over time if the underlying issues are resolved.
• Indicator, not cause: A SORBS listing is often more an indicator of poor list hygiene or sending practices rather than the direct cause of delivery problems.
• Direct submission: While delisting forms exist, some suggest direct communication with SORBS (for example, via email) for faster resolution.

Key considerations

• Verify impact: Before reacting, confirm if the SORBS listing is genuinely causing delivery issues. Use an email deliverability tester to diagnose deeper problems.
• Address root causes: Focus on improving list hygiene, consent, and sending practices to prevent future listings. This is covered in more detail in this Validity article on the SORBS Spam blocklist.
• Client vs. agency responsibility: Determine who is responsible for delisting requests, especially for shared vs. dedicated IP pools.
• Patience: Allow time for automated delisting or processing of manual requests before escalating.

Key opinions

• Minimal impact: Many marketers state that a SORBS blocklist entry typically doesn't lead to noticeable delivery problems, especially with major providers.
• Automated delisting: It's common for IPs to be automatically removed from SORBS after a period if sending behavior improves.
• Fill the form: The standard approach for delisting is to fill out the form provided by SORBS, which is generally quite responsive.
• Hygiene indicator: A listing can highlight underlying list hygiene issues, prompting marketers to review their email acquisition and management.
• Responsibility clarification: For agency clients, it's important to clarify whether the agency or the client is responsible for managing dedicated IP delisting requests.

Key considerations

• Assess actual impact: Don't panic about a SORBS listing without first verifying if it's causing actual delivery problems. A blocklist check can confirm the status, but bounces are the real indicator.
• Prioritize other issues: If delivery issues persist, look beyond SORBS to other potential causes, such as SPF, DKIM, or DMARC issues. Check our guide on email authentication.
• Communicate clearly: Ensure clear communication with clients about who is responsible for managing IP reputation, especially for shared versus dedicated IPs, as this often depends on service agreements.
• Wait and monitor: For many, waiting a week or so while monitoring deliverability is a viable strategy, as SORBS listings can resolve independently.

Key opinions

• Minor influence: Experts generally agree that SORBS has a relatively low impact on deliverability compared to more influential blocklists like Spamhaus.
• Early warning sign: A SORBS listing often acts as an early indicator of potential issues like spam trap hits or poor list quality, prompting a review of sending practices.
• Focus on root cause: If delivery problems are evident, experts advise looking beyond the SORBS listing to fundamental issues like reputation, content, or authentication, rather than just the blocklist itself.
• Direct communication: For faster resolution, contacting SORBS directly via their support email can be more effective than relying solely on automated forms.

Key considerations

• Proactive monitoring: Regularly monitor your IP reputation across various blocklists, but understand the varying impact each blocklist carries. Our blocklist checker can assist.
• Holistic deliverability view: Do not treat a SORBS listing in isolation. Integrate it into a broader understanding of your email program's health, including engagement metrics and bounce rates.
• List hygiene importance: Focus on maintaining clean mailing lists and avoiding spam traps to prevent listings on SORBS and other blocklists.
• Strategic delisting: If a SORBS listing persists and you believe it's impacting delivery, engage with them directly or seek expert assistance if needed. For general advice on contacting ISPs, see our guide.

Key findings

• SORBS definition: SORBS (Spam and Open Relay Blocking System) is a DNS-based blocklist (DNSBL) that lists IP addresses identified as sources of spam or open relays.
• Listing criteria: Listings can occur due to various reasons, including sending to spam traps, botnet activity, or improper server configurations that allow open relays.
• Delisting process: Documentation often outlines a self-service delisting process via their website, requiring verification and often a waiting period.
• Impact variability: While documented, the specific impact of a SORBS listing on email delivery can vary significantly depending on the receiving mail server's configuration.

Key considerations

• Address underlying cause: Before requesting delisting, it is critical to identify and resolve the root cause of the listing to prevent re-listing.
• Review log files: Mail server logs can provide clues regarding the activity that led to the SORBS listing.
• Compliance with standards: Ensure your email sending practices adhere to industry standards and RFCs to maintain a good sender reputation. This includes having proper DMARC records.
• ISP policies: Understand that each ISP has its own filtering policies, and not all use SORBS equally. Therefore, a SORBS listing may not affect all recipients. For example, Amazon SES documentation mentions they don't primarily rely on SORBS, as seen in this AWS discussion.