Summary
A sudden drop in email open rates, despite successful inbox placement, is often a multifaceted issue involving factors beyond just deliverability. These factors span technical aspects (email clipping, one-click unsubscribe implementation), subscriber engagement (list fatigue, content relevancy, sending frequency), domain and sender reputation, external influences (Apple's MPP, seasonal trends), and inbox provider filtering (graymail suppression). A holistic approach involving technical checks, content optimization, list management, reputation monitoring, and adaptation to privacy changes is essential for diagnosing and addressing the problem.
Key findings
- MPP Skews Open Rates: Apple's Mail Privacy Protection inflates open rates, masking true engagement.
- Content Relevance Matters: Irrelevant content leads to subscriber disengagement, impacting open rates even with good inbox placement.
- List Fatigue Reduces Engagement: Over-mailing or irrelevant content causes list fatigue, leading to lower open rates.
- Segmentation Enhances Relevance: Lack of audience segmentation results in irrelevant messaging and lower open rates.
- Frequency Affects Engagement: High sending frequency without valuable content causes subscriber burnout and reduced opens.
- Technical Factors Intervene: Email clipping and improper one-click unsubscribe setup negatively influence open rates.
- External Forces Impact Opens: Holidays and seasonal trends can affect email open rates independent of deliverability.
- Google's Unsubscribe Preference: Google prioritizes proper one-click unsubscribe implementation; non-compliance can hurt deliverability.
- Graymail Suppression Hides Emails: Inboxes may filter emails as 'graymail,' hiding them from the primary inbox due to low engagement.
- Reputation Affects Visibility: Declining domain reputation can lead to throttling or placement in less prominent inbox tabs.
- Lack of Recorded Spam Complaints: Spam complaints from spam folders do not show in postmaster tools.
Key considerations
- Monitor Domain Reputation: Consistently monitor domain reputation using tools like Google Postmaster Tools and Microsoft SNDS.
- Optimize Sending Frequency: Optimize sending frequency to avoid overwhelming subscribers with too many emails.
- Check One-Click Unsubscribe: Ensure proper implementation of one-click unsubscribe, paying close attention to HTTPS and `List-Unsubscribe-Post`.
- Test Email Rendering: Test email rendering across devices and email clients to ensure proper display and functionality.
- Review Postmaster Tools Data: Analyze recipient domain open and click data to identify issues with specific providers.
- Refine Content and Strategy: Actively collect and analyze subscriber feedback to refine content and campaign strategy.
- Segment Email List: Segment email lists based on subscriber demographics, behavior, and engagement to target messaging effectively.
- Optimize Subject Lines: Monitor and A/B test subject lines to maximize open rates and engagement.
- Avoid Email Clipping: Avoid email clipping by keeping total size under 102kb.
- Adapt to MPP: Account for MPP skewed numbers by focusing on other performance indicators like clicks.
What email marketers say
12 marketer opinions
A sudden drop in email open rates despite inbox placement can stem from various factors beyond deliverability. These include technical issues like email clipping or improper one-click unsubscribe setup, subscriber-related problems such as list fatigue or irrelevant content, external factors like Apple's MPP or seasonal trends, and sending strategy weaknesses like lack of segmentation or high frequency. Analyzing these areas provides actionable insights for improving engagement.
Key opinions
- MPP Impact: Apple's Mail Privacy Protection inflates open rates, masking actual engagement. A drop after MPP implementation may be a more accurate reflection of opens.
- Content Relevancy: Subscribers stop opening emails if the content is no longer relevant. Analyze behavior and adjust content strategy.
- List Fatigue: Decreased open rates can stem from list fatigue. Subscribers receiving too many emails disengage.
- Segmentation: Lack of segmentation leads to decreased engagement. Send relevant content based on subscriber interests.
- Sending Frequency: Increased sending frequency without valuable content can cause subscriber burnout and lower open rates.
- Technical Issues: Emails getting clipped or improper one-click unsubscribe can negatively impact open rates.
- External Factors: External factors like holidays or seasonal trends influence open rates.
- Domain Reputation: Check domain reputation with providers to see if deliverability has dropped.
Key considerations
- Check Domain Reputation: Monitor domain reputation using tools like Google Postmaster Tools and Microsoft SNDS.
- Implement One-Click Unsubscribe: Ensure proper implementation of one-click unsubscribe, including HTTPS and List-Unsubscribe-Post headers.
- Analyze Recipient Domain: Check open and click rates by recipient domain to identify issues with specific mailbox providers.
- Refine Content Strategy: Gather subscriber feedback and adjust content to align with their interests and needs.
- Segment Your List: Segment your email list based on demographics, interests, and engagement levels.
- Optimize Email Rendering: Test emails across various devices and email clients to ensure optimal rendering.
- Subject Lines: Ensure subject lines are engaging and tested for optimal performance.
- Optimize Sending Frequency: Determine an appropriate email sending frequency to avoid subscriber burnout.
Marketer view
Marketer from Email Geeks asks about the presence of `List-Unsubscribe-Post` and suggests checking server logs for Google's POST requests to the unsubscribe URL, and also to check if there any rate limiting is impacting Google POSTing to those URLs.
4 Oct 2021 - Email Geeks
Marketer view
Email marketer from Reddit suggests that increased sending frequency without providing valuable content can lead to subscriber burnout and decreased open rates. Even if emails are inboxing, subscribers may simply be overwhelmed and choose to ignore them.
18 Jul 2021 - Reddit
What the experts say
3 expert opinions
Despite emails reaching the inbox, sudden drops in open rates can be attributed to Google's one-click unsubscribe requirements, graymail suppression implemented by mailbox providers (filtering emails out of the primary inbox), or a decline in domain reputation leading to throttling or placement in less prominent tabs. Regular monitoring of domain reputation, correct implementation of one-click unsubscribe, and awareness of graymail suppression are crucial.
Key opinions
- One-Click Unsubscribe: Google prioritizes correct one-click unsubscribe implementation.
- Graymail Suppression: Mailbox providers may suppress graymail, filtering emails from primary inboxes due to low engagement.
- Domain Reputation: Declining domain reputation can cause ISPs to throttle emails or place them in less prominent tabs.
Key considerations
- Test with AboutMyEmail: Send a test email to aboutmy.email to identify potential issues.
- Monitor Domain Reputation: Regularly monitor your domain reputation with ISPs and anti-spam organizations.
- Implement One-Click Unsubscribe: Ensure correct one-click unsubscribe implementation.
- Engagement Monitoring: Actively monitor and address low engagement to avoid graymail suppression.
Expert view
Expert from Spam Resource explains that even with emails reaching the inbox, a sudden drop in open rates could signify a decline in domain reputation. ISPs might be throttling your emails or placing them in less prominent inbox tabs due to perceived reputation issues. Regularly monitor your domain reputation and ensure compliance with sending best practices.
29 Jun 2021 - Spam Resource
Expert view
Expert from Word to the Wise explains that a sudden drop in open rates despite good inbox placement can be caused by mailbox providers implementing graymail suppression. This means that emails are being delivered but filtered out of the primary inbox, effectively hiding them from users. This can be triggered by low engagement and is something senders need to actively monitor and address.
26 Jun 2022 - Word to the Wise
What the documentation says
3 technical articles
Even if emails are bypassing spam filters, a sudden drop in open rates can indicate underlying issues related to sender reputation and technical implementation. Google's documentation highlights that spam complaints aren't recorded for emails landing in spam, while Microsoft emphasizes the importance of maintaining a positive sender reputation. RFC documentation specifies the correct implementation of `List-Unsubscribe-Post`, which is crucial for deliverability. Overall, continuous monitoring of sender reputation, proper technical setup, and adherence to best practices are essential.
Key findings
- Spam Complaint Blind Spot: Spam complaints are not recorded for emails that land directly in the spam folder.
- Sender Reputation: Maintaining a positive sender reputation is crucial, even if emails reach the inbox.
- List-Unsubscribe-Post: Proper implementation of `List-Unsubscribe-Post` is essential for deliverability and user experience.
Key considerations
- Use Google Postmaster Tools: Utilize Google Postmaster Tools to check deliverability and spam rates.
- Monitor Microsoft SNDS: Use Microsoft's Smart Network Data Services (SNDS) to monitor sender reputation.
- Verify List-Unsubscribe-Post: Ensure the URL for `List-Unsubscribe-Post` is controlled by you and that Google's POST requests are handled correctly.
- Review Sending Practices: Review sending practices, authentication methods, and engagement metrics to address any issues affecting reputation.
Technical article
Documentation from Google explains that if mail lands in spam, it doesn’t record spam complaints. Google Postmaster Tools is a tool to check the deliverability and spam rate of emails sent from your domain.
4 Jan 2025 - Google
Technical article
Documentation from RFC explains about implementing `List-Unsubscribe-Post` and ensuring that the URL is a domain that can control. Also checking if logs show Google making POST requests to the URL and if yes, what's the response?
27 Aug 2023 - RFC
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