Summary
Experts, marketers, and documentation widely agree that relying solely on email open rates as a metric is increasingly problematic due to factors like Apple's Mail Privacy Protection (MPP), image blocking, and bot activity. MPP inflates open rates by pre-loading images, rendering the data less trustworthy. The consensus is to use open rates cautiously, primarily for assessing subject line performance on a limited basis. A holistic approach is recommended, emphasizing engagement metrics such as click-through rates (CTR), conversions, website traffic, revenue, and customer lifetime value (CLTV) to gain a more accurate understanding of campaign effectiveness. Segmentation, personalization, and advanced analytics play a crucial role in optimizing campaigns based on these more reliable indicators.
Key findings
- Opens Are Unreliable: Apple's MPP, image blocking, and bot activity make open rates an increasingly unreliable metric.
- MPP Inflates Data: MPP pre-loads images, inflating open rates and skewing campaign data.
- Focus on Engagement: Key metrics should shift to click-through rates, conversions, website traffic, revenue, and CLTV.
- Use Sparingly for Subject Lines: Open rates can be used cautiously to assess subject line performance, but are not definitive.
Key considerations
- Adopt Holistic Approach: Implement a holistic measurement strategy encompassing various engagement metrics.
- Leverage Advanced Analytics: Employ advanced analytics and attribution models to track the true impact of email campaigns on business outcomes.
- Implement Segmentation: Segment email lists and personalize content to drive genuine engagement.
- Adapt to Privacy: Adapt marketing strategies to align with growing privacy concerns and MPP.
What email marketers say
13 marketer opinions
Experts and marketers agree that using email opens as a sole metric for email marketing success is not sufficient. While opens can provide some insight into subject line performance and initial engagement, they are becoming increasingly unreliable due to factors like Apple's Mail Privacy Protection and image blocking. A holistic approach that considers click-through rates, conversions, website traffic, and other engagement metrics is recommended for a more accurate understanding of campaign performance. Furthermore, segmenting email lists and personalizing content can improve engagement, but negative engagement should be carefully monitored.
Key opinions
- Opens Not Sufficient: Relying solely on open rates is insufficient for measuring email marketing success.
- Opens are Unreliable: Open rates are becoming less reliable due to privacy changes and image blocking.
- Need Hollistic Approach: A holistic approach considering other engagement metrics is crucial.
- Clicks are better: Clicks are often considered a better metric than opens
Key considerations
- Track Multiple Metrics: Track click-through rates, conversions, website traffic, and other relevant metrics in addition to open rates.
- Monitor Negative Engagement: Take precautions to remove contacts with negative engagement signals (e.g., spam complaints).
- Segment Lists: Segment email lists and personalize content to improve engagement.
- A/B Test: A/B test different email elements to optimize for overall performance, not just open rates.
Marketer view
Email marketer from G2 explains that while open rates are a good starting point, marketers must consider other metrics like click-through rates, conversion rates, and bounce rates to understand the full impact of their campaigns. They recommend using analytics tools to track these metrics and gain actionable insights for optimization.
30 May 2025 - G2
Marketer view
Marketer from Email Geeks shares that using any single metric to try and measure success is just bad statistics.
19 Jan 2023 - Email Geeks
What the experts say
5 expert opinions
Experts generally agree that email opens are an increasingly unreliable metric for measuring email marketing success, particularly due to Apple's Mail Privacy Protection (MPP). MPP inflates open rates, skewing data and making it difficult to accurately assess campaign performance. Instead of focusing on opens, experts recommend shifting towards metrics that reflect user engagement and business outcomes, such as click-through rates (CTR), conversions, customer lifetime value (CLTV), and revenue.
Key opinions
- Opens are Unreliable: Apple's Mail Privacy Protection (MPP) makes open rates less trustworthy.
- Focus on Actions: Marketers should measure actions that are important to them, like revenue and conversions.
- Opens can be harmful: Using opens without considering feedback loops can lead to reputation problems.
Key considerations
- Shift to Engagement Metrics: Shift focus towards metrics like click-through rates, conversions, and customer lifetime value.
- Implement Advanced Analytics: Use advanced analytics and attribution models to track the true impact of email campaigns.
- Adapt to Privacy Changes: Adapt email marketing strategies to account for privacy changes like Apple's MPP.
Expert view
Expert from Word to the Wise suggests that marketers should shift their focus from open rates to metrics like click-through rates (CTR), conversions, and customer lifetime value (CLTV) in a post-MPP world. They recommend using advanced analytics and attribution models to track the true impact of email campaigns on business outcomes.
21 Oct 2023 - Word to the Wise
Expert view
Expert from Email Geeks explains that using opens as a metric for who to continue mailing without also having FBLs to identify which of those opens resulted in a this is spam hit, leads to an increase in mail to folks who don’t want it and/or are receiving the message in their spamfolder, which longer term can lead to reputation problems.
19 Dec 2021 - Email Geeks
What the documentation says
4 technical articles
Email marketing documentation consistently emphasizes that open rates are becoming increasingly unreliable as a primary metric for email marketing success due to privacy changes like Apple's Mail Privacy Protection (MPP) and image blocking. While open rates can offer some insight into subject line effectiveness and initial interest, they should be used with caution. A greater emphasis should be placed on analyzing other metrics like click-through rates, conversion rates, website traffic, read time, and overall engagement levels to get a more accurate understanding of how recipients are interacting with email campaigns. It's important to use email testing and analytics tools to optimize email design and content for better engagement.
Key findings
- Opens Less Reliable: Open rates are becoming less reliable due to MPP and image blocking.
- MPP Inflates Rates: Apple's Mail Privacy Protection can inflate open rates, skewing data.
- Subject Line Effectiveness: Open rates can still offer *some* insight into subject line effectiveness, but not as a primary measure.
Key considerations
- Focus on Other Metrics: Focus on metrics like click-through rates, conversion rates, website traffic, read time, and engagement levels.
- Use Analytics Tools: Utilize email testing and analytics tools to optimize email design and content.
- Cautious Use of Opens: Use open rates cautiously and in conjunction with other metrics.
Technical article
Documentation from Litmus suggests that open rates should be used cautiously due to factors like Apple's Mail Privacy Protection and image blocking. They recommend focusing on metrics like click-through rates, read time, and engagement levels to gain a more accurate understanding of how recipients are interacting with emails. They also suggest using email testing and analytics tools to optimize email design and content for better engagement.
22 Oct 2023 - Litmus
Technical article
Documentation from Mailchimp explains that open tracking is a feature that allows users to see how many recipients opened their email. It uses an embedded invisible image, and when the image is downloaded it's recorded as an open. However, they also highlight that open rates are becoming less reliable due to privacy changes like Apple's Mail Privacy Protection.
10 Apr 2022 - Mailchimp
Do email clicks improve inbox deliverability?
How accurate are seed lists for email deliverability testing?
How accurate is email client market share data when Apple Mail intentionally opens messages?
How do AI assistants and MPP impact email open rates, and what are better metrics to measure outbound campaign effectiveness?
How do Mail Privacy Protection (MPP) and Intelligent Tracking Prevention (ITP) affect click tracking in email marketing?
Is email tracking dead and should marketers stop using open rates?
