Why has my email open rate decreased recently?

Key findings

• ISP tracking changes: Some ISPs and email clients are evolving their methods for counting opens, often filtering out non-human (bot) interactions or anonymizing tracking, which can lead to a perceived drop without a true change in user behavior.
• Sender reputation: A decline in sender reputation (due to spam complaints, high bounce rates, or blocklist appearances) can cause emails to land in spam folders or be blocked entirely, directly impacting open rates. You can assess your standing using Google Postmaster Tools for Gmail deliverability.
• Content and engagement: Decreased relevance of content, repetitive subject lines, or sending too frequently can lead to subscriber fatigue and lower engagement, causing fewer emails to be opened.
• List hygiene: An unclean or old email list can accumulate inactive subscribers, spam traps, and invalid addresses, all of which contribute to lower open rates and can negatively affect your sender reputation. Regularly cleaning your list is key.
• Competitive inbox: Especially during peak seasons like Black Friday, the sheer volume of emails competing for attention in the inbox can naturally suppress open rates.

Key considerations

• Data accuracy: Verify with your ESP how they calculate open rates. Ask if they have implemented any recent changes in filtering non-human interactions or bot opens. This is a common reason for a sudden drop without a change in subscriber behavior, as highlighted by Word to the Wise.
• Email authentication: Ensure your email authentication records (SPF, DKIM, DMARC) are correctly configured. Failing authentication can lead to emails being sent to spam or rejected, affecting your deliverability and opens. Review our guide to DMARC, SPF, and DKIM for more.
• Segmented analysis: Investigate if the drop is consistent across all ISPs (e.g., Gmail, Outlook, Yahoo) or concentrated in a specific one. This can help narrow down the problem, as different ISPs have varying filtering algorithms. Sometimes, drops are ISP-specific.
• Engagement patterns: Analyze if the drop correlates with specific email types (e.g., promotional, transactional), subject lines, sending times, or audience segments. This can reveal issues with content strategy or audience relevance.
• Blocklist status: Regularly check if your sending IP or domain has been added to any major blocklists or blacklists. Being listed on a blocklist can severely impede your deliverability and thus, your open rates. Utilize a blocklist checker.

Key opinions

• Competition: Many marketers attribute drops in open rates to increased competition for inbox space, especially during busy periods like the lead-up to Black Friday.
• ESP calculation changes: There's a strong sentiment that ESPs may be changing how they calculate open rates, potentially filtering out non-human or automated opens, leading to artificially lower reported numbers even if actual human engagement remains stable.
• Content relevance: When drops are not ISP-specific, marketers often suspect issues with the email content itself. This includes subject lines, themes, and whether the content has been repeated too often.
• Audience targeting: Some marketers confirm seeing overall drops despite targeting only engaged users with highly relevant content, suggesting broader industry shifts or ESP policy changes may be at play.
• Sudden significant drops: A drop from 22% to 8% is considered significant and warrants immediate investigation, as it often points to a serious deliverability or engagement problem.

Key considerations

• Investigate ISP specifics: Even if the overall open rate drops, checking for specific ISP patterns (e.g., a disproportionate drop in Gmail) can help diagnose the issue. This is crucial as Gmail changes often impact broad segments.
• ESP transparency: Marketers should proactively ask their ESPs if they have adjusted how they count opens, particularly regarding the filtering of non-human interactions.
• Content and timing analysis: Conduct a detailed analysis of the affected emails. Look for commonalities in subject lines, content themes, sending days, and times to identify potential triggers for the decline. Sometimes a simple subject line change can reverse drops.
• Audience engagement strategy: Re-evaluate segmentation and targeting. Ensure that emails are sent to the most engaged subscribers and that the content aligns with their expectations to improve overall engagement and prevent further drops.
• Broader trends: Be aware that widespread shifts in email privacy, such as Apple's Mail Privacy Protection (MPP), can globally impact reported open rates, making true engagement harder to measure via traditional methods. For more on how to approach these types of problems check out how to fix declining rates.

Key opinions

• ESP filtering changes: Experts commonly suggest that ESPs are increasingly filtering out non-human image loads (bot activity) from open metrics to provide more accurate engagement data. This can cause a reported drop even if human behavior remains consistent.
• Measurement quality: Some drops in open rates may reflect ESPs improving the quality of their reported numbers by removing inflated, non-human opens, rather than a true decline in audience interest.
• Inbox placement issues: If emails are consistently landing in spam or the promotions tab (e.g., in Gmail), this will directly lead to lower open rates, regardless of subject line quality.
• Deliverability impact: Significant drops can indicate underlying deliverability problems, such as sender reputation issues or blocklistings, which prevent emails from reaching the primary inbox.
• Privacy changes: Industry-wide privacy changes, particularly Apple's Mail Privacy Protection, have significantly altered how open rates are tracked, often leading to a general decline in reported opens.

Key considerations

• Inquire about open rate calculation: It is paramount to ask your ESP whether they differentiate between human and non-human interactions when reporting open metrics, and if their methodology has recently changed. This is frequently a key area, as discussed by experts at Word to the Wise.
• Monitor inbox placement: Focus on actual inbox placement rather than solely relying on open rates, especially since privacy changes affect open tracking. Tools like email deliverability testers can provide more accurate insights.
• Address spam issues: If emails are going to spam, identify and rectify the root causes, which could include content, sender reputation, or authentication issues. Our guide, why your emails are going to spam, offers solutions.
• Understand domain reputation: A low domain reputation directly correlates with lower open rates as ISPs are less likely to deliver your emails to the primary inbox. Continuously work on building and maintaining a strong sender reputation.
• Adopt new metrics: With the diminishing accuracy of open rates, experts advise focusing on other engagement metrics like click-through rates, conversions, and replies to gauge campaign effectiveness more reliably.

Key findings

• Privacy enhancements: Initiatives like Apple's Mail Privacy Protection (MPP) pre-fetch images, artificially inflating or skewing open rates and making traditional open tracking unreliable for affected users.
• Authentication standards: Major email providers (e.g., Gmail, Yahoo) increasingly enforce strict authentication (SPF, DKIM, DMARC) for bulk senders. Failure to comply leads to higher spam placement or outright rejection, severely impacting opens.
• Reputation algorithms: ISPs use complex algorithms to assess sender reputation based on engagement, complaints, and bounce rates. A dip in reputation can trigger stricter filtering, reducing inbox placement and, consequently, measured opens.
• Spam trap hits: Hitting spam traps indicates poor list hygiene and can severely damage sender reputation, leading to blocklistings and reduced deliverability to the inbox (and therefore, lower open rates).
• Content filtering: Spam filters analyze email content, including subject lines, body text, and links, for suspicious patterns. Triggering these filters can lead to emails being diverted to spam, impacting opens.

Key considerations

• Adherence to new sender requirements: Ensure full compliance with new sender requirements from major mailbox providers, particularly concerning authentication and one-click unsubscribe, to maintain strong deliverability.
• DMARC implementation: Implement and monitor DMARC policies (at `p=quarantine` or `p=reject`) to protect your domain from spoofing and enhance sender reputation, crucial for consistent inbox placement. Use a DMARC record generator if needed.
• Engagement-based sending: Prioritize sending to highly engaged segments to signal positive behavior to ISPs, thereby improving overall deliverability and potentially mitigating the impact of privacy changes on reported opens.
• Regular blocklist checks: Systematically check against major blacklists and blocklists, as inclusion on these lists can cause significant deliverability failures leading to sharp declines in open rates. Consider blocklist monitoring.
• Content optimization for deliverability: Design emails to be deliverability-friendly, avoiding practices that trigger spam filters (e.g., excessive links, poor HTML, certain spammy keywords) to ensure they reach the inbox effectively.