Why are Gmail open rates lower when emails land in tabs other than the inbox?

Key findings

• Visibility matters: Emails landing in tabs like 'Promotions' or 'Updates' are less likely to be seen immediately compared to those in the 'Primary' tab. This reduced visibility can naturally lead to lower observed open rates, even if the email avoids the spam folder.
• Prefetching theory: Some experts hypothesize that Gmail, similar to Apple Mail Privacy Protection (MPP) and Yahoo, may prefetch images in the primary inbox, artificially inflating open rates there. This prefetching might not occur in other tabs, causing a perceived drop in opens. Zettasphere suggests that low open rates are more often due to junk folder placement than the promotions tab.
• Engagement versus placement: Lower open rates in non-primary tabs do not always correlate with lower revenue per email. Users might be more receptive to marketing messages in the 'Promotions' tab, knowing what to expect, potentially leading to better quality engagement, even if the initial open rate is lower.
• Reporting inconsistencies: The way Email Service Providers (ESPs) report open rates, especially in light of MPP and varying image prefetching behaviors across different Mailbox Providers (MBPs), can contribute to discrepancies. It's crucial to understand how your ESP calculates and presents these metrics.

Key considerations

• Focus on engagement metrics: Beyond open rates, prioritize metrics like click-through rates, conversions, and revenue per email to get a more accurate picture of campaign success. A low open rate in a secondary tab might still yield good results if the content is relevant to the audience expecting it there. You can also explore how to improve low Gmail email open rates generally.
• Content and user expectations: Align your email content with the tab it's likely to land in. Promotional content naturally fits the 'Promotions' tab. Trying to force it into 'Primary' might lead to user complaints and negatively impact your sender reputation, which is far worse than tab placement.
• Monitor placement: Regularly check where your emails are landing using seed list testing or inbox placement tools. This helps confirm whether the emails are indeed reaching the intended tabs or if there's a more serious deliverability issue (like landing in spam or on a blacklist). Email Industries suggests that emails landing in the promotions tab might have lower open and click-through rates.
• A/B testing and main sends: Be aware that A/B tests on smaller segments might not accurately reflect deliverability for larger main sends, especially concerning Gmail's tab sorting algorithms which evaluate sender reputation and content patterns over time.

Key opinions

• Perceived drop in opens: Marketers frequently report a 10-30% drop in open rates when emails are classified into tabs other than the primary inbox. This is often attributed to reduced immediate visibility.
• Not spam, but still a concern: The primary concern is often the lower open rate, rather than the email being marked as spam. Tools used for inbox placement testing confirm that even if an email lands in a tab, it's still considered delivered to the inbox.
• A/B test vs. main send: Discrepancies between A/B test results and main send performance are common, with main sends showing disproportionately lower open rates. This can create anxiety about campaign performance.
• Mailchimp reporting: ESPs like Mailchimp may report all opens without distinguishing between actual user engagement and potential prefetching by Mailbox Providers (MBPs), complicating accurate analysis of true human opens.
• Promotions tab benefits: Some marketers find the promotions tab useful, as it allows users to intentionally engage with promotional content at their convenience, potentially leading to higher quality interactions. Ontraport Blog noted that the Promotions tab is less problematic than initially thought, only lowering open rates by about one percent on average.

Key considerations

• Monitor tab placement: Actively monitor where your emails are landing in Gmail. This insight helps differentiate between tab placement issues and more serious deliverability problems, such as emails being sent to the spam folder. Knowing why your emails are going to the promotions tab is the first step.
• Adjust performance expectations: Recognize that a drop in open rates for emails in non-primary tabs may be a new baseline rather than an indicator of a major issue. Focus on conversion rates and overall ROI.
• Content strategy: Tailor your content and sender behavior to influence tab placement, though this is not always within complete control. Understand the impact of Gmail's tabs on deliverability.
• Data analysis: Be diligent in analyzing your email data. Separate primary tab opens from other tab opens if possible, and look for correlations between tab placement and actual business outcomes, not just vanity metrics.

Key opinions

• Prefetching beyond Apple: Experts confirm that Apple Mail Privacy Protection (MPP) isn't the only system prefetching images. Yahoo actively engages in this, and there's strong anecdotal evidence that Gmail does it for the primary inbox as well, though it's not officially confirmed.
• Open rate discrepancies: There are clear differences in open rates between the primary and promotions tabs, even without corresponding differences in revenue per email. This suggests a reporting artifact rather than a true decline in engagement or deliverability.
• Promotions tab's role: Some experts theorize that Gmail might intentionally avoid prefetching in the promotions tab to provide marketers with more 'accurate' open data, distinguishing it from the potentially inflated primary tab opens.
• Data interpretation: The interpretation of open rate data needs to evolve beyond simple numerical comparisons. Understanding the context of tab placement and prefetching is essential for accurate performance assessment. For more on this, see our article on why your email deliverability rate is wrong.

Key considerations

• Adapt to evolving metrics: Deliverability professionals must adapt their measurement strategies. Relying solely on open rates, especially for campaigns targeting Gmail users, can be misleading due to automatic image loading and tab sorting. Focus on clicks and conversions.
• Segmented engagement: Recognize that users interact differently with emails in various tabs. The promotions tab attracts users looking for deals, which can lead to higher quality, albeit fewer, engagements for relevant content. This might even improve overall deliverability rates.
• Continuous monitoring: Ongoing monitoring of email placement and engagement trends across different Gmail tabs is crucial. This helps identify shifts in filtering behavior and allows for proactive adjustments to sending strategies. Our email deliverability test can help.
• Holistic view of reputation: While open rates may fluctuate, a consistently good sender reputation (based on factors like low complaints, consistent volume, and proper authentication like DMARC, SPF, and DKIM) remains paramount for long-term deliverability. You can gain more insight through Google Postmaster Tools.

Key findings

• User experience focus: Gmail's primary goal is to provide users with a clean and organized inbox. The tabbed interface is designed to help users manage their email flow more effectively by categorizing messages based on their content and sender type.
• Content and sender signals: Gmail's filtering algorithms consider numerous signals, including sender reputation, content analysis, user interactions (opens, clicks, replies, marks as spam), and historical sending patterns, to determine optimal inbox placement, including tab assignment. This includes assessing why emails appear in the wrong Gmail tab.
• Bulk sender guidelines: Google's sender guidelines for bulk senders emphasize authentication (SPF, DKIM, DMARC), low spam rates, and sending to engaged users. Adherence to these guidelines improves overall deliverability and a sender's chances of reaching the desired tab.
• Promotions tab features: Google has actively introduced features for the Promotions tab (e.g., image bundles, deal carousels) to enhance the user experience and encourage engagement within that tab, implicitly suggesting it's a valid and intended destination for commercial messages.

Key considerations

• Authenticate properly: Ensure your emails are fully authenticated with SPF, DKIM, and DMARC. This is a foundational requirement for good deliverability and helps Gmail trust your sending domain. Learn more about DMARC, SPF, and DKIM.
• Monitor sender reputation: Utilize tools like Google Postmaster Tools to monitor your domain and IP reputation. These metrics provide direct feedback from Gmail about your sending health, which is a major factor in tab placement and overall deliverability. This will give you insights into how to improve domain reputation.
• Engage your audience: Focus on sending relevant, valuable content to an engaged audience. High user engagement (opens, clicks) and low complaint rates signal to Gmail that your emails are desired, which can positively influence placement. Gmail's guidelines highlight the importance of user experience.
• Content optimization: While no exact formula exists to guarantee primary tab placement, avoiding overly promotional language, excessive images, and common marketing triggers can sometimes influence placement. However, it's often more beneficial to embrace the tab where your content belongs.