Why is Gmail deliverability down despite good reputation?

Summary

Even with a strong sender reputation, Gmail deliverability can suffer due to a multitude of factors. These include technical issues like pixel clipping, rendering errors, and broken authentication (SPF, DKIM, DMARC); problems with email content such as spam trigger words or problematic links; poor list hygiene, resulting in sending to unengaged users, invalid addresses or spam traps; sudden changes in sending behavior; low recipient engagement; or violating Google's sending guidelines. The age and reputation of the sending IP address also matters. Monitoring Google Postmaster Tools and responding to feedback loops is crucial, but it's equally important to optimize content, maintain a clean list, and adhere to authentication standards.

Key findings

  • Content Risks: Specific links or spam trigger words can bypass reputation and directly trigger filters.
  • Technical Configuration Matters: Issues like pixel clipping, rendering errors, and broken SPF, DKIM, and DMARC can hurt deliverability regardless of overall reputation.
  • List Health Is Key: Sending to old, unengaged, or invalid addresses significantly damages deliverability.
  • Engagement Is A Ranking Factor: Low open and click-through rates can signal to Gmail that your emails are not valuable.
  • Sending Patterns Count: Sudden shifts in sending volume can trigger spam filters.
  • Reputation Has Nuances: Previously used or shared IPs may have a negative history affecting deliverability.
  • Google's Guidelines are Paramount: Violating Google's sender guidelines (e.g., high spam complaint rates, unsolicited emails) can override a good reputation.
  • Feedback Loops Are Critical: Ignoring feedback loops and spam complaints can erode deliverability over time.

Key considerations

  • Audit Email Content: Regularly review email content for spam trigger words, suspicious links, and high image-to-text ratios.
  • Check Technical Setup: Ensure proper email authentication (SPF, DKIM, DMARC) and troubleshoot any rendering or coding issues.
  • Practice List Hygiene: Implement a process for regularly cleaning your email list and removing unengaged subscribers.
  • Segment and Personalize: Segment your audience and personalize your email content to increase engagement rates.
  • Monitor Sending Volume: Gradually increase sending volume and avoid sudden spikes in email frequency.
  • Investigate IP Reputation: If using a shared IP address, monitor its reputation and consider using a dedicated IP for greater control.
  • Comply with Guidelines: Thoroughly understand and adhere to Google's sender guidelines to avoid being flagged as a spammer.
  • Monitor Feedback Loops: Actively monitor feedback loops and address spam complaints to improve your sending reputation.
  • Utilize Postmaster Tools: Regularly check Google Postmaster Tools for detailed insights into your sending reputation and deliverability.

What email marketers say
10Marketer opinions

Despite a good sender reputation, Gmail deliverability can be negatively impacted by various factors, including email content, sending practices, and recipient engagement. Technical issues like clipped pixels, rendering errors, and authentication problems also play a role. Furthermore, list hygiene, IP address history, and the degree of personalization influence whether emails reach the inbox.

Key opinions

  • Content Matters: Email content, including spam trigger words, image-to-text ratio, and broken links, can trigger spam filters even with a good sender reputation.
  • Engagement is Crucial: Low subscriber engagement, such as low open and click-through rates, signals to Gmail that emails are not valuable, leading to deliverability issues.
  • Authentication is Key: Inconsistent or improperly configured email authentication (SPF, DKIM, DMARC) can negatively impact deliverability.
  • List Hygiene is Essential: Poor list hygiene, including sending to old, unengaged addresses and spam traps, can hurt your sender reputation.
  • Sending Practices Influence: Sudden changes in sending volume, frequency, or content can raise red flags with Gmail.
  • Technical Factors Play a Role: Issues with email rendering, coding errors, and clipped tracking pixels can trigger spam filters.

Key considerations

  • Optimize Content: Review email content for spam trigger words, ensure a balanced image-to-text ratio, and fix broken links.
  • Improve Engagement: Segment your audience, personalize your emails, and provide valuable content to increase engagement rates.
  • Authenticate Emails: Ensure SPF, DKIM, and DMARC are properly configured to authenticate your emails.
  • Clean Your List: Regularly remove unengaged subscribers and invalid email addresses from your list.
  • Monitor Sending Behavior: Avoid sudden changes in sending volume, frequency, or content that could raise red flags with Gmail.
  • Test Email Rendering: Test your emails across different email clients and devices to ensure proper rendering and avoid coding errors.
Marketer view

Email marketer from Sendinblue shares that while a good sender reputation is crucial, consistent email authentication (SPF, DKIM, DMARC), list hygiene (removing inactive subscribers), and providing value to recipients are essential for maintaining Gmail deliverability. Inconsistencies in these areas can lead to deliverability issues even with a positive reputation.

April 2024 - Sendinblue
Marketer view

Email marketer from Email Geeks suggests that the issue may be a result of the pixel being clipped at Gmail on new templates. In addition, the marketer suggests checking conversion rates to see if there's a dip.

March 2022 - Email Geeks
Marketer view

Email marketer from Reddit shares that poor list hygiene is a common cause of deliverability problems, even for reputable senders. Sending emails to old, unengaged addresses or spam traps can hurt your sender reputation and lead to Gmail filtering emails as spam.

March 2024 - Reddit
Marketer view

Email marketer from Email on Acid explains that issues with email rendering and coding can trigger spam filters. Errors in HTML code, especially with preview text, can cause emails to be flagged as spam, impacting deliverability regardless of sender reputation.

May 2024 - Email on Acid
Marketer view

Email marketer from Mailjet explains that despite a good sender reputation, the content of the emails themselves can trigger spam filters. Using spam trigger words, having a high image-to-text ratio, or including broken links can negatively affect deliverability and cause emails to land in the spam folder.

April 2024 - Mailjet
Marketer view

Email marketer from Neil Patel's Blog explains that even with a good sender reputation, factors like poor email content, sending frequency, and recipient engagement can negatively impact Gmail deliverability. Low engagement signals to Gmail that the emails are not valuable to recipients, leading to placement in the spam folder despite a good reputation.

May 2021 - Neil Patel's Blog
Marketer view

Email marketer from StackOverflow answers that a previously used or shared IP address might have a poor reputation. Even if the current sender has a good sending reputation, the IP address's past history can affect deliverability at Gmail.

January 2023 - StackOverflow
Marketer view

Email marketer from Litmus shares that lack of personalization and segmentation can lead to low engagement, which can signal to Gmail that emails are not valuable, even if sender reputation is good. Generic, un-targeted emails are more likely to be filtered as spam.

May 2024 - Litmus
Marketer view

Email marketer from HubSpot shares that low subscriber engagement rates, such as low open rates and click-through rates, can cause deliverability issues even with a good reputation. Gmail considers engagement metrics when determining where to place emails.

August 2024 - HubSpot
Marketer view

Email marketer from ActiveCampaign shares that sudden changes in sending volume, frequency, or content can raise red flags with Gmail. Even with a good reputation, drastic shifts in sending behavior can trigger spam filters and negatively impact deliverability.

February 2024 - ActiveCampaign

What the experts say
4Expert opinions

Even with a good sender reputation, Gmail deliverability issues can arise due to problems with specific email content, authentication, and list quality. A single problematic link can trigger spam filters, highlighting the importance of email content scrutiny. While Google Postmaster Tools is the authoritative source for reputation data, it's important to recognize that emails with problematic elements can still be marked as spam. Furthermore, authentication issues, particularly with SPF and DKIM alignment, and poor list quality resulting from unengaged addresses, invalid emails or spam traps further damage deliverability.

Key opinions

  • Content Can Trigger Spam Filters: A single problematic link within an email can cause Gmail to flag the email as spam, regardless of overall sender reputation.
  • Postmaster Tools is Authoritative but Not a Guarantee: While Google Postmaster Tools provides the best data on your reputation, emails can still be marked as spam if they contain problematic elements.
  • Authentication is Crucial: Authentication issues (SPF/DKIM) can cause deliverability problems even with good reputation. Gmail is strict on authentication.
  • List Quality Matters: Poor list quality (unengaged, invalid addresses, spam traps) can damage reputation and harm deliverability despite other sending activities.

Key considerations

  • Scrutinize Email Content: Carefully review all links and content in emails to avoid triggering spam filters.
  • Monitor Postmaster Tools: Use Google Postmaster Tools to monitor your sender reputation and identify potential issues.
  • Ensure Proper Authentication: Verify SPF and DKIM records are correctly configured and aligned.
  • Maintain List Hygiene: Regularly clean your email list by removing unengaged subscribers, invalid addresses, and spam traps.
Expert view

Expert from Email Geeks states that Google Postmaster Tools is the authoritative source for understanding reputation with Google, and also clarifies that emails can still be marked as spam even with a high reputation if the email contains problematic elements.

April 2024 - Email Geeks
Expert view

Expert from Word to the Wise explains that poor list quality, meaning sending to addresses that are unengaged, invalid, or spam traps, damages your sender reputation. This harms deliverability at Gmail despite your other sending activities.

September 2024 - Word to the Wise
Expert view

Expert from Word to the Wise explains that authentication issues, particularly with SPF and DKIM alignment, can cause deliverability problems even with a good sender reputation. She also notes that Gmail is increasingly strict about authentication.

May 2023 - Word to the Wise
Expert view

Expert from Email Geeks suggests a potential cause for Gmail deliverability issues: a specific link in the email might have triggered Gmail's spam filters. She also notes that this could be an isolated incident or the beginning of a decline in reputation.

January 2022 - Email Geeks

What the documentation says
4Technical articles

Even with a good sender reputation, Gmail deliverability can be compromised by factors such as violating Google's sender guidelines (sending unsolicited emails or high spam complaint rates), misconfigured or missing SPF records for email authentication, absent or improperly configured DMARC policies, and failure to monitor and respond to feedback loops (FBLs). While sender reputation is crucial, adhering to email best practices and properly configuring technical aspects of email sending are essential for ensuring deliverability.

Key findings

  • Reputation Isn't Everything: Even senders with high reputation can experience deliverability issues if they violate Google's sender guidelines (unsolicited emails, high spam complaint rate).
  • SPF Configuration is Critical: Misconfigured or incomplete SPF records can cause Gmail to treat emails as suspicious, impacting deliverability despite good reputation.
  • DMARC Policy Matters: Absent or improperly configured DMARC policies increase the likelihood of Gmail filtering emails as spam, even with a good sender reputation.
  • Feedback Loops Are Important: Failure to monitor and respond to feedback loops can lead to missed spam complaints, negatively impacting deliverability despite a good initial reputation.

Key considerations

  • Adhere to Sender Guidelines: Ensure compliance with Google's sender guidelines to avoid being flagged for sending unsolicited emails or generating high spam complaint rates.
  • Verify SPF Records: Confirm SPF records are correctly configured and include all authorized sending sources.
  • Implement DMARC Policy: Implement and properly configure a DMARC policy to protect against email spoofing and phishing attacks.
  • Monitor Feedback Loops: Actively monitor and respond to feedback loops to address spam complaints and improve email practices.
Technical article

Documentation from RFC explains that SPF records are critical for email authentication. If an SPF record is not properly configured, or if it does not include all sending sources, Gmail may treat emails as suspicious, leading to deliverability issues despite a good overall sender reputation.

March 2025 - RFC
Technical article

Documentation from Microsoft explains the concept of feedback loops (FBLs). If a sender is not actively monitoring and responding to FBLs, they may be unaware of spam complaints, which can negatively impact their reputation and deliverability, even if their initial reputation was good.

April 2021 - Microsoft Documentation
Technical article

Documentation from Google Postmaster Tools Help explains that sender reputation is a key factor for deliverability, but it's not the only one. Even senders with a high reputation can experience deliverability issues if their emails violate Google's sender guidelines, such as sending unsolicited emails or having a high spam complaint rate.

July 2023 - Google Postmaster Tools Help
Technical article

Documentation from DMARC.org explains that a DMARC policy helps protect against email spoofing and phishing attacks. If a domain does not have a DMARC policy in place, or if the policy is not properly configured, Gmail may be more likely to filter emails as spam, even if the sender has a good reputation.

May 2022 - DMARC.org