What could be causing email delivery problems to Gmail despite consistent open rates?
Matthew Whittaker
Co-founder & CTO, Suped
Published 20 May 2025
Updated 16 Aug 2025
6 min read
It can be perplexing when you see consistent open rates for your emails, yet you're still experiencing delivery problems to Gmail. We often associate a high open rate with good inbox placement, so a disconnect like this signals that something more nuanced might be at play.
The primary issue here is typically not about whether recipients are interested in your content, but rather about the technical signals and underlying reputation metrics that determine if Gmail delivers your emails to the inbox at all. Gmail's filtering algorithms are highly sophisticated, constantly evaluating multiple factors beyond just opens.
I've seen many senders struggle with this, and it often boils down to a few key areas that require close attention. Understanding these can help diagnose and resolve the hidden deliverability issues impacting your Gmail performance.
Understanding sender reputation beyond open rates
Even with seemingly good engagement, your sender reputation could be suffering from issues that aren't immediately visible through open rates alone. Google (Google) places a strong emphasis on user engagement and complaint rates. A low complaint rate is crucial, as even a small percentage of spam complaints can significantly harm your standing with Gmail. This is why consistently monitoring your metrics, especially within Google Postmaster Tools, is vital.
Your IP and domain reputations are distinct but interconnected factors. While your domain reputation is critical and directly reflects your brand's sending practices, IP reputation can also play a role, especially if you're on a shared IP address. If other senders on the same shared IP have poor practices, it could negatively impact your deliverability, even if your domain reputation is strong.
Another often overlooked aspect is the health of your email list itself. Sending to invalid or unengaged addresses can lead to bounces and a higher likelihood of hitting spam traps, which can dramatically lower your sender score. Regularly cleaning your list is a foundational step for maintaining good standing with mailbox providers.
Why is this happening?
Hidden signals: Consistent open rates might indicate recipients are opening your emails, but Gmail also considers other less visible engagement metrics.
Reputation factors: Your overall sender reputation, influenced by factors like spam complaints and bounce rates, impacts whether your emails reach the inbox or the spam folder.
Technical authentication and false opens
Email authentication is no longer optional, especially with the latest guidelines from Gmail and Yahoo. If your SPF, DKIM, and DMARC records are not correctly configured or aligned, Gmail may still deliver your emails, but they might be placed in the spam folder or subject to delivery delays. This can happen even if recipients are opening them, as opens might be triggered by pre-fetching email clients or simply not indicate proper inbox placement.
DMARC, in particular, is critical because it tells recipient servers how to handle emails that fail SPF or DKIM authentication. Without a robust DMARC policy, spoofed emails can be sent using your domain, negatively impacting your reputation and potentially leading to your legitimate emails being flagged as spam. Ensure your DMARC record is correctly set up and monitored.
I've seen cases where emails appear to have good open rates, but upon closer inspection of deliverability reports, a significant portion was actually going to the spam or junk folder. The open rate measurement itself can sometimes be misleading due to privacy features in some email clients or the use of pixel tracking.
Incorrect configuration
Improperly configured SPF, DKIM, or DMARC records can lead to delivery issues, even if your content is engaging. Gmail prioritizes authenticated mail. If your emails fail these checks, they are more likely to land in the spam folder.
Misleading open rate metrics
Some email clients, particularly on mobile, pre-fetch images in emails, which can artificially inflate open rates. This means an email might be 'opened' without ever reaching the recipient's primary inbox, or even being seen by the user.
Content, list quality, and sending patterns
Beyond technical setup, the very content of your emails can trigger Gmail's spam filters, even if your sender reputation is generally good. Certain keywords, excessive use of links, image-to-text ratio, and even suspicious formatting can all contribute to emails being flagged. It's not just about what you say, but how you say it and how it's presented.
Another factor is the relevance and consistency of your sending patterns. Sending inconsistent volumes or drastically changing your content strategy can raise red flags. Gmail prefers to see predictable and consistent sending behavior from reputable domains. If your emails suddenly change in nature, it can be a sign of compromise or a shift to less desired sending practices.
The source of your email addresses also significantly impacts deliverability. If you're using lists that aren't purely opt-in, or if you're not regularly removing unengaged subscribers, you're exposing yourself to spam traps and lower engagement signals, regardless of your open rates. A clean, engaged list is the cornerstone of good deliverability.
Content and formatting
Emails with poor image-to-text ratios, broken links, or suspicious formatting can trigger spam filters, regardless of sender reputation.
Sender reputation
A history of high complaint rates, even if current ones are low, can result in your emails being placed in the spam folder by Gmail.
List hygiene
Sending to unengaged subscribers or invalid email addresses can lead to increased bounces and spam trap hits, hurting your deliverability.
Sending behavior
Sudden spikes in sending volume or changes in content that deviate from past behavior can be seen as suspicious by mailbox providers.
Moving beyond surface metrics
If you're facing consistent open rates but still seeing deliverability issues, it's time to dig deeper than superficial metrics. Focus on the foundational elements of email deliverability. This includes rigorously enforcing email authentication, segmenting your audience effectively, and maintaining impeccable list hygiene.
We often advise senders to look at their complete email ecosystem, from DNS records to recipient engagement. It's a holistic approach that truly moves the needle for inbox placement, especially with a vigilant provider like Gmail.
By addressing these underlying factors, you can transition from simply having emails 'opened' to ensuring they consistently land where they belong: the primary inbox. This shift in focus is essential for long-term email marketing success.
Views from the trenches
Best practices
Implement strong email authentication (SPF, DKIM, DMARC) and monitor their alignment for all sending domains.
Regularly clean your email lists to remove inactive subscribers, hard bounces, and known spam traps.
Monitor your complaint rates closely using Google Postmaster Tools and other feedback loops.
Segment your audience based on engagement and send targeted content to active subscribers.
Common pitfalls
Relying solely on open rates as a deliverability metric, which can be inflated by pre-fetching.
Ignoring low engagement or high complaint rates reported by Google Postmaster Tools.
Sending emails to purchased or old lists that contain unengaged or invalid addresses.
Neglecting to consistently monitor IP and domain reputation on major blocklists (or blacklists).
Expert tips
Use a dedicated IP address if your sending volume justifies it, giving you more control over your reputation.
Pay close attention to domain reputation, as it is often a leading indicator for Gmail delivery issues.
Analyze engagement beyond just opens, focusing on clicks, replies, and emails moved to folders.
Understand that Gmail's algorithms prioritize true engagement, not just perceived opens.
Expert view
Expert from Email Geeks says open rates might be consistent due to Gmail pre-fetching pixels, but domain reputation should be the primary focus for dedicated IPs to monitor deliverability changes. IP reputation can be a trailing factor, and problems with reaching the inbox might not be immediately visible from opens.
2024-03-15 - Email Geeks
Expert view
Expert from Email Geeks says the source of email addresses for campaigns like cart abandonment is crucial, asking if the mail is opt-in. They emphasize that Google's complaint rate, available directly from Google Postmaster Tools, is a key metric to check.
2024-03-16 - Email Geeks
Key takeaways
Navigating Gmail's intricate filtering system requires a multifaceted approach. While consistent open rates might offer a superficial sense of security, they can obscure deeper deliverability challenges, especially if emails are landing in the spam folder or experiencing delays. The key is to look beyond just opens.
By focusing on strong authentication, managing your sender reputation carefully, maintaining a healthy email list, and optimizing content, you can significantly improve your Gmail deliverability. Remember, successful email delivery is about earning trust with mailbox providers and ensuring your messages consistently reach the primary inbox.
For ongoing insights and specific troubleshooting, regularly consulting your Google Postmaster Tools data and understanding your domain reputation will provide the clearest path to resolving these issues.
Google) places a strong emphasis on user engagement and complaint rates. A low complaint rate is crucial, as even a small percentage of spam complaints can significantly harm your standing with Gmail. This is why consistently monitoring your metrics, especially within Google Postmaster Tools, is vital.
