How to troubleshoot and address a dropping email sender score?

Key findings

• Proprietary scores: Sender score, such as the one provided by Return Path, is a proprietary metric. It reflects delivery to domains that share data with Return Path, rather than a universal indicator of your reputation across all ISPs (internet service providers).
• Limited influence: While historically used by some ISPs, many no longer heavily rely on sender score for filtering decisions. This suggests that a drop in this specific score might not directly translate to widespread deliverability issues, particularly if other metrics are good.
• Uptick in volume: An unexpected increase in email volume, even for transactional emails, can sometimes trigger reputation flags if not managed carefully, especially with a new IP or domain.
• Other metrics are key: If bounce rates remain low and delivered versus sent percentages are high, the core email deliverability might still be strong despite a sender score dip. However, it's crucial to look beyond just these basic metrics.

Key considerations

• Holistic view: Do not solely rely on a single sender score. A comprehensive view of your email program includes analyzing engagement metrics, spam complaint rates, and whether your emails are landing in the inbox or spam folders.
• Engagement analysis: Investigate if there is a drop in engagement (opens, clicks) for your transactional emails, as this is a stronger indicator of recipient perception and deliverability health. You can learn more about troubleshooting sudden email open rate declines.
• Inbox placement testing: Regularly run inbox placement tests to see where your emails are actually landing across various mailbox providers. This provides a real-world snapshot of your deliverability, which is more critical than a theoretical score.
• Volume consistency: While transactional emails often have fluctuating volumes, a sudden, significant increase could still be perceived negatively if your infrastructure or recipient engagement isn't prepared for it. For guidance on improving deliverability, explore technical solutions for email deliverability. Consider using Sender Score's own tools to get a high-level view of your IP's reputation.

Key opinions

• Questionable utility: Many marketers express skepticism about the direct value of sender score as a primary metric for client reporting, viewing it as potentially misleading or overly simplistic.
• Return Path's proprietary nature: The understanding that sender score is a proprietary metric from Return Path, reflecting data shared only with them, diminishes its perceived universality and impact on broader deliverability.
• Lagging indicator: For some, a sender score might be a lagging indicator, meaning that if it drops, there are usually more critical underlying issues that need immediate attention first, such as sudden drops in email delivery rates.
• Focus on fundamentals: Marketers frequently advise returning to fundamental deliverability checks: monitoring bounces, delivered vs. sent rates, and crucially, email engagement.

Key considerations

• Don't panic: A drop in sender score, particularly if other core metrics (like bounce and delivery rates) are stable, may not be an immediate cause for alarm, but rather a prompt to investigate further.
• Inboxing reports: Proactively running inboxing reports is highlighted as a practical way to confirm actual deliverability across diverse mailbox providers, providing a more reliable health check than a single score.
• Check engagement: For transactional emails, confirm whether engagement (opens, clicks, unsubscribes) has also dropped, as this would indicate a more serious issue that requires attention. This helps identify the cause of declining email deliverability.
• List hygiene: Marketers frequently emphasize the importance of maintaining a clean email list to prevent issues that can negatively impact sender reputation and lead to deliverability problems. More on this can be found at Mailgun's guide to sender reputation.

Key opinions

• Beyond sender score: Experts advise that a single sender score, while a data point, should not be the primary focus. Real deliverability is determined by multiple factors, including engagement with recipients and adherence to best practices.
• Engagement is king: Mailbox providers prioritize user engagement. A sudden drop in sender score might be a symptom of declining opens, clicks, or an increase in deletes without opening, and even spam complaints. This is often central to troubleshooting high soft bounce rates.
• List hygiene criticality: Sending to inactive or invalid email addresses can severely impact your sender reputation, leading to lower scores and increased filtering, regardless of email volume. Learn about spam traps and how they work.
• Authentication standards: Ensuring proper implementation of SPF, DKIM, and DMARC is fundamental for establishing sender legitimacy and maintaining a good reputation with mailbox providers.

Key considerations

• Segment and monitor: Segment your email lists and monitor the performance of each segment. This helps identify if reputation issues are localized to specific groups of recipients or are more widespread.
• Warm-up new IPs/domains: If increasing volume significantly or using new sending infrastructure, follow a gradual IP/domain warming schedule to build reputation slowly and avoid sudden drops in score.
• Address blocklistings: Check if your sending IPs or domains have been added to any public blocklists or blacklists. Getting listed can severely impact deliverability and, consequently, sender scores. Use a reputation checker tool to identify issues.
• Consistency matters: Maintain consistent sending volume and content quality over time. Erratic sending patterns or sudden changes in content can negatively affect how mailbox providers perceive your email stream and fix sender reputation issues.

Key findings

• Authentication standards: Documentation frequently stresses the necessity of correctly implementing SPF, DKIM, and DMARC records to verify sender identity and prevent spoofing. Failures in these areas can drastically lower sender reputation.
• Content quality: Email content that resembles spam, uses excessive links, or includes blacklisted terms can trigger filters and negatively affect reputation, regardless of other factors.
• List management: Maintenance of a clean and engaged subscriber list is paramount. High bounce rates, especially hard bounces, and hitting spam traps, are clear indicators of poor list hygiene. For more information, read this guide on repairing sender reputation.
• User interaction: Positive engagement (opens, clicks, replies) boosts sender reputation, while negative signals (spam complaints, unsubscribes, deletions without opening) severely harm it. Mailjet offers a guide to sender reputation.

Key considerations

• Compliance with policies: Adhering to the specific policies and guidelines of major ISPs (Google, Yahoo, Microsoft) is crucial. Non-compliance can lead to throttled sending or direct filtering.
• Volume consistency: Mailbox providers prefer consistent sending volumes. Sudden spikes in volume, even for legitimate mail, can be interpreted as suspicious activity if not properly warmed up.
• Monitoring FBLs: Signing up for and monitoring feedback loops (FBLs) from major mailbox providers allows senders to receive direct reports on spam complaints, enabling prompt action to remove disgruntled subscribers.
• Proactive monitoring: Regularly checking your IP and domain against public blocklists and monitoring your sending infrastructure (e.g., mail logs for errors) is essential for early detection of issues.