Why did my email open rates drop after a template redesign, but click rates remained the same?
Matthew Whittaker
Co-founder & CTO, Suped
Published 25 Jul 2025
Updated 14 Aug 2025
9 min read
Summary
A sudden drop in email open rates, especially after a template redesign, can be concerning, even if click rates remain stable. This situation often points to deliverability issues rather than content quality problems, as users are still engaging with the email when it reaches their inbox. Key factors to investigate include changes in email size impacting tracking pixel visibility, how internet service providers (ISPs) perceive new or altered templates, and the accuracy of open rate metrics themselves.
Key findings
Tracking pixel issues: The location of the tracking pixel within the email, especially if it's at the bottom, can affect open rate measurement if the email size exceeds certain thresholds and gets clipped by email clients like Gmail. Accurately measuring opens without relying solely on image pixels is becoming increasingly important.
Template changes impact: Even minor HTML changes can cause ISPs to treat a message as new or different, potentially triggering spam filters or affecting initial inbox placement. This can explain why new templates might lead to deliverability issues, particularly with Gmail which accounts for a large portion of many audiences.
Engagement versus delivery: Stable click rates, despite lower opens, suggest that the content itself is still engaging for those who receive and open the email. The core problem appears to be getting the email into the inbox in the first place.
Statistical validation: It is crucial to use a statistical significance calculator to confirm if observed changes are truly significant or merely random fluctuations.
Key considerations
Data granularity: Obtain a breakdown of metrics by recipient email client (e.g., Gmail, Yahoo) to pinpoint if the drop is isolated to specific providers. This can help confirm whether Gmail's handling of the new template is the primary cause.
Tracking pixel placement: Investigate if your email service provider (ESP) allows control over the tracking pixel's placement. Moving it closer to the top of the email might ensure it loads even if the message is truncated.
Email size and clipping: Verify the total HTML payload size of your new template. Even if you don't see the message clipped link, a large email could still affect the loading of elements at the bottom.
Wait for data: Resist the urge to theorize extensively before concrete data, such as per-client breakdowns, becomes available. Data-driven decisions are always more effective.
Click rate calculation: Confirm how your click rates are calculated. If they are based on opens rather than sent emails, a drop in opens would naturally lead to fewer clicks overall, even if the click-to-open rate (CTOR) remains high.
What email marketers say
Email marketers grappling with a drop in open rates after a template redesign, while click rates hold steady, often point to a disconnect between content appeal and deliverability. Many suspect that changes, even minor ones, can cause ISPs to treat emails differently, impacting inbox placement. The focus shifts to technical aspects like tracking pixel reliability and the true meaning of 'open' in modern email environments.
Key opinions
New template impact: A common belief is that any significant change to an email template can negatively affect how ISPs initially perceive and route messages, even if no infrastructure changes occurred.
Tracking pixel vulnerability: There is concern that the tracking pixel, especially if placed at the end of a long email, might not load if the email client truncates the message, leading to underreported open rates. This is a crucial factor in improving Gmail open rates.
Subject line consistency: While the template changed, maintaining the same approach to subject lines and preheaders is generally seen as a positive, as it keeps one engagement factor consistent.
Open rate measurement: Some marketers question the reliability of open rates as a standalone metric, particularly if click rates remain stable, suggesting the core issue might be delivery rather than engagement. Understanding how to increase click-through rates becomes paramount in such cases.
Key considerations
Statistical validation: Always use statistical significance to confirm if the drop is a real trend or just noise, especially with small observation periods. A sudden drop in open rate should be thoroughly investigated.
Client-specific analysis: Breakdown open rates by email client to isolate the problem. If Gmail users are a large portion of the audience, their behavior can skew overall stats.
Tracking image placement: Consider repositioning the tracking pixel higher up in the email's HTML structure, if your ESP allows, to ensure it loads before any clipping occurs.
Metric calculation method: Double-check whether click rates are calculated based on total sent emails or only on opened emails, as this significantly impacts interpretation when open rates decline.
Marketer view
An email marketer from Email Geeks shared their recent experience, noting that about a week and a half after launching a new redesigned email template, their daily open rates significantly dropped while click rates remained largely unchanged. They are observing the numbers by day of the week to analyze the impact.
12 Feb 2020 - Email Geeks
Marketer view
An email marketer from the Constant Contact Community indicates that a compelling subject line is crucial for attracting opens. They suggest testing different sending days and times, and reviewing content to ensure it is not too repetitive or similar, as these factors can lead to decreased engagement over time.
15 Feb 2020 - Constant Contact Community
What the experts say
Email deliverability experts highlight that open rate data is inherently complex and often unreliable, particularly due to changing client behaviors like image caching and privacy features. They emphasize that any significant change to an email's content or structure can impact its perceived reputation by ISPs. The stability of click rates, in contrast to dropping opens, strongly suggests an inbox placement issue rather than a lack of subscriber interest.
Key opinions
Open data unreliability: Experts agree that open data is often horribly handled and can be misleading, especially with advancements in privacy like Apple Mail Privacy Protection, which often trigger pixels without actual opens.
ISPs and content changes: Any change to an email, even just the HTML template, can cause ISPs to treat it as bad or unfamiliar, potentially affecting deliverability and inbox placement.
Tracking pixel visibility: If the HTML payload size increases substantially, the tracking image (often at the bottom) could be missed if the email is clipped, even if the visible clipping notification isn't shown.
Engagement signals: ISPs prioritize emails that users demonstrate a desire to receive. Consistency in positive engagement signals helps improve overall deliverability.
Key considerations
Data breakdown: It is essential to analyze data by recipient MX (mail exchange) to understand if specific providers are responsible for the open rate drop.
Tracking pixel hostname: Ensure your tracking pixel is hosted on a different hostname from your main images to avoid browser connection throttling issues that could delay its loading.
Message size limits: While 100kb is a common threshold for Gmail clipping, it's vital to monitor email size. Tracking images placed at the bottom are more vulnerable to not loading if the message approaches or exceeds this limit.
Patience and observation: Allow sufficient time (more than a week) for data to stabilize after a significant template change before drawing firm conclusions. Some ISPs might take time to adjust to new patterns.
Expert view
A deliverability expert from Email Geeks suggests that stable click rates despite decreased opens indicate that the initial focus should be on obvious factors. They question if the tracking image handler or URL changed, or if the tracking image might be lost if the message is truncated by Gmail due to its size.
12 Feb 2020 - Email Geeks
Expert view
An email deliverability expert from SpamResource.com advises that email providers often use a combination of engagement metrics, including opens and clicks, to determine inbox placement. They note that a sudden shift in template might trigger algorithms to re-evaluate sender reputation, leading to initial filtering.
20 Apr 2024 - SpamResource.com
What the documentation says
Technical documentation and industry resources emphasize that email template redesigns, particularly those increasing HTML payload size or introducing new image elements, can subtly affect deliverability. While open rates are a key metric, their accuracy can be compromised by various factors, including how email clients render messages and track engagement. The documentation suggests that engagement metrics like clicks are more reliable indicators of content value once an email reaches the inbox.
Key findings
Open rate importance: Despite challenges in measurement, open rates remain a critical metric for understanding email campaign performance and diagnosing potential issues, serving as an early indicator of deliverability problems. Further information on email deliverability issues is essential.
Content design and clicks: Cluttered email designs are a significant reason for low click-through rates. Documentation stresses that recipients tend to skim emails, requiring clear and concise layouts to drive engagement.
Factors for low opens: A multitude of factors, not just template design, can lead to low open rates, including subject line effectiveness, sending reputation, and email list hygiene. Understanding what causes sudden drops is key.
Subscriber list quality: Inactive or invalid email addresses on a list are direct contributors to low open rates and can damage sender reputation over time. Maintaining a clean list is paramount.
Key considerations
Holistic optimization: Optimizing email strategy for better results requires considering various elements, from content relevance and subject lines to email list quality and sending practices.
Benchmark comparison: Regularly compare email marketing statistics against industry benchmarks to assess performance and identify areas for improvement.
Clarity over clutter: Prioritize clear and uncluttered email designs to enhance readability and encourage click-throughs, recognizing that users often skim emails rather than reading them thoroughly.
Deliverability strategy: Understand that a decrease in opens can directly indicate bulking or blocking issues at the ISP level, necessitating a review of the entire deliverability strategy.
Technical article
Documentation from Beehiiv Blog asserts that understanding email open rates and their impact on deliverability is critical for optimizing email strategies. They highlight the importance of dissecting trends and changes in these rates to gain actionable insights into performance.
10 Apr 2024 - Beehiiv Blog
Technical article
Mailchimp's resources encourage marketers to compare their email marketing statistics against industry benchmarks. This comparison helps in understanding current performance and identifying areas where improvements can be made to better align with industry averages.
