Why has my email deliverability dropped significantly, despite a low spam rate and bounce rate, and what steps can I take to resolve it?

Summary

A significant drop in email deliverability despite low spam and bounce rates is a complex issue stemming from various factors. Insufficient explicit permission, poor list hygiene (including old, inactive emails, and spam traps), blacklisting due to spam practices or poor sender reputation, authentication failures (SPF, DKIM, DMARC), problematic content triggering spam filters, changes in email algorithms, and technical issues like incorrect DNS settings all contribute. Analyzing metrics using tools like Google Postmaster Tools is crucial. Solutions involve verifying explicit consent, improving list hygiene through cleaning and segmentation, actively monitoring and improving sender reputation, implementing and monitoring email authentication protocols, reviewing email content for spam triggers, adapting to changes in email marketing practices, and ensuring relevance and value in email content. Consistently monitoring email metrics and adapting to changes in email algorithms is essential for sustained deliverability.

Key findings

  • List Hygiene: Poor list hygiene, including old or inactive emails and spam traps, is a major cause of deliverability problems.
  • Blacklisting: Being blacklisted significantly impacts deliverability, often due to spam practices or poor sender reputation. Check using tools like MXToolbox.
  • Authentication: Incorrect or missing email authentication (SPF, DKIM, DMARC) leads to deliverability problems. Implement and monitor these protocols.
  • Content: Email content triggering spam filters harms deliverability. Avoid spam trigger words and misleading subject lines.
  • Algorithmic Changes: Email algorithms change frequently, requiring continuous monitoring and adaptation of email marketing practices.
  • Technical Issues: Technical problems, like incorrect DNS settings, can cause sudden deliverability drops. Double-check recent website changes.
  • Explicit Permission: Inadequate explicit permission from subscribers negatively impacts deliverability. Ensure subscribers actively opt-in.
  • Google Postmaster Tools: Google Postmaster Tools provides data on spam rate, IP reputation, and domain reputation, which are critical indicators of deliverability issues.
  • Deferred Messages: Deliverability may be skewed due to deferred messages which have not yet bounced, which will give a false initial delivery percentage.

Key considerations

  • Verify Consent: Ensure clear and verifiable consent from subscribers to receive emails. Review list collection processes.
  • Review List Practices: Regularly clean and segment email lists to remove inactive or problematic addresses. Consider segmentation based on engagement and demographics.
  • Monitor Reputation: Use tools like Google Postmaster Tools and MXToolbox to monitor sender and IP reputation and check for blacklist listings.
  • Implement Authentication: Ensure proper implementation and monitoring of SPF, DKIM, and DMARC records. Use DMARC to dictate how mailboxes handle failed authentication.
  • Optimize Content: Review email content for spam trigger words, relevance, and clear communication.
  • Monitor Metrics: Consistently monitor email metrics (bounce rates, spam complaints, engagement) and adapt to changes in email algorithms. Monitor unsubscribe rates and reasons.
  • Investigate Configuration: Double-check recent website or email configuration changes that may affect deliverability.
  • Email Segmentation: Review your current segmentation. Segmentation is all about dividing subscribers into smaller groups based on similar criteria.

What email marketers say
10Marketer opinions

A significant drop in email deliverability despite low spam and bounce rates can stem from various interconnected issues. These include problems with list hygiene (old, inactive emails, spam traps), blacklisting due to poor sender reputation or sending practices, authentication failures (SPF, DKIM, DMARC), content triggering spam filters, changes in email algorithms, and technical issues like incorrect DNS settings. Solutions involve improving list hygiene through cleaning and segmentation, actively monitoring and improving sender reputation, implementing and monitoring email authentication protocols, reviewing email content for spam triggers, and adapting to changes in email marketing practices.

Key opinions

  • List Hygiene: Poor list hygiene, including old or inactive emails and spam traps, is a common cause of deliverability issues.
  • Blacklisting: Being blacklisted can significantly impact deliverability, often due to spam practices or poor sender reputation.
  • Authentication: Incorrect or missing email authentication (SPF, DKIM, DMARC) can lead to deliverability problems.
  • Content: Email content that triggers spam filters can harm deliverability.
  • Algorithmic Changes: Changes in email algorithms can affect deliverability, requiring ongoing monitoring and adaptation.
  • Technical Issues: Technical problems, such as incorrect DNS settings, can cause sudden deliverability drops.
  • Deferred Messages: Deliverability may be skewed due to deferred messages which have not yet bounced, which will give a false initial delivery percentage.

Key considerations

  • Review List Practices: Regularly clean and segment email lists to remove inactive or problematic addresses.
  • Monitor Reputation: Use tools like Google Postmaster Tools and MXToolbox to monitor sender and IP reputation, and check for blacklist listings.
  • Implement Authentication: Ensure proper implementation and monitoring of SPF, DKIM, and DMARC records.
  • Optimize Content: Review email content for spam trigger words, excessive capitalization, and misleading subject lines.
  • Monitor Metrics: Consistently monitor email metrics (bounce rates, spam complaints, engagement) and adapt to changes in email algorithms.
  • Investigate Configuration: Double-check recent website or email configuration changes that may affect deliverability.
  • Explicit Permission: Ensure you have explicit permission to send emails to your subscribers, not just inferred or assumed.
  • Email Segmentation: Review your current segmentation. Segmentation is all about dividing subscribers into smaller groups based on similar criteria.
Marketer view

Email marketer from Reddit shares personal experience: a sudden drop happened after a recent website update that inadvertently changed some DNS settings affecting SPF. Suggests double-checking recent changes to website or email configuration.

August 2022 - Reddit
Marketer view

Marketer from Email Geeks explains that an 80% delivery rate usually implies a 20% bounce rate, so the numbers don't initially make sense. He suggests deferred messages could be the reason if messages are retried until their maximum time has lapsed, leading to a later influx of bounces. Mentions that being listed at Spamhaus typically indicates issues with bot sign-ups, old data, or using a bought list.

November 2021 - Email Geeks
Marketer view

Email marketer from Sendinblue responds that consistently monitoring email metrics and adapting to changes in email algorithms is essential for sustained deliverability. Suggests using a dedicated IP address, warming up new IPs gradually, and personalizing email content to engage recipients.

May 2024 - Sendinblue
Marketer view

Email marketer from Neil Patel explains that a sudden drop in deliverability despite good metrics can be due to changes in email marketing practices, IP reputation, or authentication issues. Recommends checking sender reputation, authenticating email (SPF, DKIM, DMARC), reviewing content for spam triggers, and segmenting email lists.

September 2022 - Neil Patel
Marketer view

Email marketer from StackOverflow states to use tools like MXToolbox to check your domain and IP against blacklists. Also recommends reviewing feedback loops if available to see if recipients are marking your messages as spam.

August 2022 - StackOverflow
Marketer view

Marketer from Email Geeks explains that low spam complaint rates could indicate emails are already going to spam. Suggests looking at unsubscribe rates and reasons for insights. Advises reviewing list collection processes for mistyped domains. Recommends contacting Spamhaus, highlighting they are generally helpful if you demonstrate efforts to solve the underlying issue.

December 2023 - Email Geeks
Marketer view

Email marketer from EmailGeeks responds that blacklists can impact your email deliverability and prevent your emails from reaching their intended recipients. They suggest that being on a blacklist can happen for various reasons, including sending spam, having a poor sender reputation, or using outdated or inaccurate email lists. They recommend checking your domain against blacklists, identifying the reasons for being blacklisted, and taking steps to address the underlying issues.

October 2023 - EmailGeeks
Marketer view

Email marketer from Mailjet shares that deliverability problems can arise from various sources, including poor list hygiene (old or inactive emails), spam traps, and blacklisting. Suggests cleaning email lists, monitoring sender reputation with tools like Google Postmaster Tools, and improving email authentication.

April 2023 - Mailjet
Marketer view

Email marketer from EmailVendorSelection explains that not all subscribers are the same. They joined at different times, in different ways and have different levels of engagement with your emails. Segmentation is all about dividing subscribers into smaller groups based on similar criteria. They suggest different types of segmentation based on behaviour, demographics and purchase history.

June 2021 - EmailVendorSelection
Marketer view

Email marketer from Kickbox explains that email list cleaning or validation is the process of removing invalid, inactive, or problematic email addresses from your mailing list. It helps improve email deliverability, sender reputation, and engagement rates. They recommend regularly cleaning your email list to reduce bounce rates, spam complaints, and the risk of being blacklisted.

July 2024 - Kickbox

What the experts say
4Expert opinions

Email deliverability drops, even with low spam and bounce rates, can arise from inadequate explicit permission to send emails, problematic content, and a lack of proper email authentication. Sufficient and verifiable consent is crucial, as is ensuring email content avoids spam triggers and provides value. Robust email authentication (SPF, DKIM, DMARC) is also necessary for establishing sender credibility. Good list hygiene is essential - ensuring you email to individuals that actually want to receive your emails.

Key opinions

  • Explicit Permission: Insufficient explicit permission from subscribers can negatively impact deliverability, even with low spam and bounce rates.
  • Content Impact: Email content with spam trigger words, misleading subject lines, or a lack of value hurts deliverability.
  • Authentication Importance: Proper email authentication (SPF, DKIM, DMARC) is vital for building credibility with mailbox providers and avoiding spam filters.
  • List Hygiene: Good list hygiene is essential - ensuring you email to individuals that actually want to receive your emails.

Key considerations

  • Verify Consent: Ensure you have clear and verifiable consent from subscribers to receive emails.
  • Optimize Content: Review email content for spam triggers, relevance, and clear communication.
  • Implement Authentication: Implement and monitor SPF, DKIM, and DMARC records for improved authentication.
  • Maintain List Hygiene: Review your email list often and remove any subscribers who have not opted in or are unengaged.
Expert view

Expert from Spamresource explains that content plays a critical role in deliverability. Avoid using spam trigger words, excessive capitalization, or misleading subject lines. Ensure your email content is relevant, valuable, and clearly communicates the purpose of the message.

June 2021 - Spamresource
Expert view

Expert from Spamresource explains that deliverability issues despite low bounce and complaint rates can stem from insufficient explicit permission. Inferred or assumed permission is not enough; subscribers must actively opt-in to receive your emails. Ensure clear consent is obtained before sending any messages.

September 2023 - Spamresource
Expert view

Expert from Word to the Wise explains that that the single, most effective way to improve email deliverability is with good list hygiene. This means that you email to individuals that actually want to receive your emails, this requires ongoing effort.

August 2023 - Word to the Wise
Expert view

Expert from Word to the Wise responds that proper email authentication (SPF, DKIM, DMARC) is vital for establishing credibility with mailbox providers. Without it, legitimate emails may be flagged as suspicious and sent to spam. Implement and monitor authentication records to improve deliverability.

May 2021 - Word to the Wise

What the documentation says
5Technical articles

Email deliverability issues, despite low spam and bounce rates, can be investigated and resolved by understanding and implementing key email authentication protocols and monitoring tools. Google Postmaster Tools offers valuable data on spam rates and sender reputation. SPF, DKIM, and DMARC are essential authentication methods for verifying sender identity and preventing forgery, enhancing trust with mailbox providers like Gmail and Outlook.com. Proper implementation of these standards contributes to improved deliverability.

Key findings

  • Google Postmaster Tools: Google Postmaster Tools provides critical metrics for assessing and improving email deliverability, especially for Gmail users.
  • SPF Authentication: SPF prevents spammers from using forged 'from' addresses, contributing to better email authentication.
  • DMARC Policy: DMARC builds upon SPF and DKIM, providing policy and reporting mechanisms for email authentication and handling authentication failures.
  • DKIM Verification: DKIM uses digital signatures to verify sender identity and message integrity, improving deliverability and preventing phishing.
  • Microsoft Best Practices: Microsoft has best practices for getting your emails delivered to outlook.com

Key considerations

  • Analyze Metrics: Use Google Postmaster Tools to analyze spam rates, IP reputation, and domain reputation to identify deliverability issues.
  • Implement SPF: Configure SPF records in DNS to specify authorized sending sources for your domain.
  • Implement DMARC: Implement DMARC policies to dictate how mailbox providers should handle emails that fail authentication checks.
  • Implement DKIM: Use DKIM to sign outbound emails, providing verification of sender identity and message integrity.
  • Follow Microsoft Best Practices: Check Microsoft documentation and follow best practices for getting your emails delivered to outlook.com
Technical article

Documentation from RFC Editor explains that SPF (Sender Policy Framework) is an email authentication method that helps prevent spammers from sending messages with forged 'from' addresses at your domain. Specifies the technical implementation of SPF records in DNS.

November 2021 - RFC Editor
Technical article

Documentation from Microsoft responds with Email deliverability best practices for Outlook.com

November 2024 - Microsoft
Technical article

Documentation from DMARC.org responds that DMARC (Domain-based Message Authentication, Reporting & Conformance) builds on SPF and DKIM to provide policy and reporting mechanisms. DMARC allows senders to indicate that their emails are protected by SPF and/or DKIM, and tells receivers what to do if authentication fails, such as reject the message.

June 2023 - DMARC.org
Technical article

Documentation from Google explains that Google Postmaster Tools provides data on spam rate, IP reputation, and domain reputation, which are critical indicators of deliverability issues. Recommends analyzing these metrics to identify and address underlying problems affecting email delivery to Gmail users.

September 2021 - Google
Technical article

Documentation from DKIM.org explains that DKIM (DomainKeys Identified Mail) is an email authentication method that uses a digital signature to verify the sender's identity and ensure the message hasn't been altered during transit. It helps to improve email deliverability and prevent phishing attacks.

June 2022 - DKIM.org