What to do when a client is blacklisted by Verizon?

Key findings

• IP-specific blocking: Verizon's blacklisting often targets specific IP addresses, even when an organization uses a pool of IPs. This can result in some IPs delivering normally while others are completely blocked, leading to a zero percent open rate without bounces on the affected IPs.
• Challenges with delisting: Engaging with Verizon's support can be difficult, with reports of tickets being closed prematurely or refusals to reset reputations, even for clients with generally good sending practices. This can feel like a dead end when an ISP postmaster is unresponsive.
• Effectiveness of IP switching: A surprising number of cases show that switching to an unused or old dedicated IP address can immediately restore deliverability to Verizon in certain scenarios, especially for senders who don't genuinely deserve to be blocklisted.
• Reputation persistence: Even for seemingly minor infractions or a single unpopular message, an IP's reputation with Verizon can be severely impacted and slow to recover, indicating a sensitive and reactive filtering system.

Key considerations

• Client behavior assessment: Differentiate between clients who genuinely have poor sending practices and those experiencing a temporary or misattributed reputation issue. Remediation efforts should align with the client's actual behavior.
• IP warm-up and rotation: If IP switching proves effective, ensure the new IP is properly warmed up, even if it's an old one, and monitor its performance closely. Consider strategic IP rotation for high-volume senders.
• Ongoing monitoring: Continuously monitor delivery to Verizon and other major ISPs. Keep a close watch on metrics like open rates, bounce rates, and complaint rates to detect reputation issues early.
• Persistent communication: Despite challenges, maintain a log of all interactions with Verizon support. Document all attempts at communication and their responses, which may be useful if escalation becomes necessary.

Key opinions

• Client accountability: Many marketers agree that if a client's practices truly warrant a blocklist placement, fundamental changes in their sending behavior are necessary, or they might even need to be removed from the platform if they refuse to improve. Knowing how to manage senders and identify the cause is crucial.
• Surprising IP effectiveness: There is consistent surprise at how quickly switching to a previously unused IP can restore deliverability, particularly for Verizon Media properties, even when the blocked IP has been problematic for weeks.
• Verizon support frustrations: Marketers frequently report issues with Verizon's support closing tickets citing unresponsiveness, even when responses were sent, leading to a perception that Verizon is disengaging from the delisting process.
• Reputation reset challenges: While some senders may find a partner or ESP that can influence Verizon to reset reputation, this is not a guaranteed path and often requires significant leverage.

Key considerations

• Short-term workarounds: For clients with good overall practices but temporary blocklisting, leveraging alternative or unused IPs can provide immediate relief and maintain email flow.
• Ongoing monitoring of new IPs: When switching IPs, diligently monitor deliverability to ensure the new IP doesn't eventually fall victim to the same filtering if underlying sending practices aren't truly pristine. Filters can catch up to bad streams over time.
• Advocacy and escalation: If Verizon's support is uncooperative, look for alternative channels or influential contacts within the industry or through larger ESPs who may have direct lines of communication to Verizon's postmaster team.
• Root cause analysis: For clients who genuinely had a problematic campaign, conduct a thorough root cause analysis to identify what triggered the negative sentiment (e.g., content, list source, frequency) and implement corrective actions.

Key opinions

• Nuance of IP reputation: Experts highlight that Verizon's IP reputation system is highly dynamic and responsive to negative signals, leading to rapid blocklisting of specific IPs. This requires detailed monitoring to discern whether a block is IP-specific or broader.
• Slow reputation recovery: Even after corrective actions are taken, Verizon's systems can be slow to improve an IP's reputation. This necessitates patience and consistent positive sending to rebuild trust over time, requiring strategies to recover domain reputation.
• Proactive relationship building: While challenging, building direct relationships with ISP postmasters, or working through larger ESPs with established contacts, can sometimes aid in reputation resets for legitimate senders.
• Beyond surface-level fixes: Simply switching IPs might offer temporary relief, but experts warn that persistent deliverability issues require a deep dive into list quality, content, sending frequency, and authentication (SPF, DKIM, DMARC) to prevent future blocklisting, and to expedite email delisting.

Key considerations

• Holistic deliverability audits: Conduct comprehensive audits of all sending practices, including list hygiene, bounce management, complaint rates, and engagement metrics, to identify and rectify underlying issues contributing to reputation problems.
• Segmented sending strategies: For clients with diverse sending needs, consider segmenting traffic across different IPs or sending platforms to isolate potential issues and protect overall sending reputation.
• Detailed logging and analysis: Maintain meticulous records of delivery attempts, bounce codes, and user feedback. This data is critical for understanding patterns, identifying triggers for blocklisting, and presenting a case to ISPs if direct delisting is attempted.
• Engagement and feedback loops: Prioritize user engagement and actively participate in feedback loops provided by ISPs to quickly address complaints and mitigate negative impacts on sender reputation.

Key findings

• Importance of authentication: Robust implementation of SPF, DKIM, and DMARC is fundamental for proving sender legitimacy and reducing the likelihood of being flagged as spam or blocklisted, as detailed in various RFCs and ISP guidelines.
• Reputation is dynamic: ISP documentation confirms that IP and domain reputation are continuously evaluated based on sending behavior, recipient engagement, and abuse complaints. A single bad campaign can have a significant negative impact.
• Bounce handling and list hygiene: Properly handling bounces (especially hard bounces) and maintaining a clean email list are explicitly stated as critical practices to prevent blocklistings and improve deliverability. Bounce codes, like 554 errors from Verizon, signal reputation issues.
• Feedback loop participation: Many ISPs encourage or require senders to register for their feedback loops to receive direct notifications of spam complaints, allowing for rapid removal of disengaged recipients.

Key considerations

• Adherence to AUP: Always review and comply with the Acceptable Use Policy (AUP) of the specific ISP you are sending to, as these policies outline forbidden sending behaviors that can lead to immediate blacklisting.
• Transparent sender identification: Ensure your sending domains and IP addresses are properly configured with reverse DNS (rDNS) and that your email headers clearly identify the sender, as this aids in reputation assessment.
• Permission-based sending: Documentation consistently stresses the importance of explicit consent (permission-based marketing) from recipients. Sending to unconfirmed or purchased lists is a primary cause of deliverability issues, explaining why emails go to spam.
• Resource management: Understand that ISPs protect their resources from malicious or abusive traffic. High bounce rates, spam complaints, or sending to spam traps can trigger automated defenses designed to protect recipient inboxes and network integrity.