Why are multiple subscribers unsubscribing at the same time?

Summary

Simultaneous unsubscribes can be caused by a combination of technical, policy, and user-related factors. Technical issues include improperly implemented one-click unsubscribe headers triggering security software, Microsoft Safe Links preemptively visiting links, and broken unsubscribe links. Mailbox providers and email platforms also play a role through automated actions like purging unengaged subscribers, implementing spam filters, or responding to complaint spikes. Furthermore, sender practices such as poor list hygiene, irrelevant content, high sending frequency, non-compliance with regulations like GDPR, and a declining sender reputation can also prompt mass unsubscribes. Bot activity also plays a significant role. Lastly, user behavior such as sudden frequency changes or mismatched content with their initial expectations can trigger the subscribers to leave.

Key findings

  • Technical Issues: Improper one-click unsubscribe implementation, Safe Links, and broken links contribute to unsubscribes.
  • Platform Automation: Mailchimp, Gmail, and other platforms automate list cleaning and spam filtering.
  • Sender Practices: List hygiene, content relevance, sending frequency, and regulatory compliance impact unsubscribes.
  • Reputation Problems: Drops in sender reputation can trigger aggressive unsubscribes.
  • User expectations: Ensure your practices match your subscribers expecations.
  • Bot Activity: Bots can trigger unsubscribe links and/or skew data.

Key considerations

  • Technical Review: Thoroughly review and test one-click unsubscribe implementations, Safe Links configurations, and ensure all links are working.
  • List Maintenance: Regularly clean your email list to remove inactive subscribers and invalid addresses.
  • Targeted Content: Segment your audience and tailor content to their interests and needs.
  • Compliance Checks: Ensure full compliance with GDPR, CCPA, and other relevant privacy regulations.
  • Reputation Monitoring: Continuously monitor sender reputation and address any deliverability issues promptly.
  • Audience Monitoring: Continuously monitor audience data and behaviour to ensure content matches their needs and wants.

What email marketers say
9Marketer opinions

Multiple subscribers unsubscribing simultaneously can stem from various factors, including automated actions by spam filters or security software at the organizational level, bot activity clicking unsubscribe links, and poor list hygiene. Sending irrelevant content, sending too frequently, not adhering to privacy regulations like GDPR, a decline in sender reputation, broken unsubscribe links, or changes in sending habits can also prompt mass unsubscribes.

Key opinions

  • Automated Unsubscribes: Spam filters or security software might automatically unsubscribe multiple users.
  • Bot Activity: Bots can trigger unsubscribe links.
  • Aggressive Spam Filters: Organizations may use spam filters that automatically unsubscribe users to protect employees.
  • List Hygiene: Poor list hygiene (old/stale addresses) leads to mass unsubscribes.
  • Irrelevant Content/Frequency: Irrelevant content or excessive sending frequency can prompt mass unsubscribes.
  • Regulatory Non-Compliance: Not adhering to GDPR/privacy regulations results in unsubscribes.
  • Sender Reputation: A drop in sender reputation can cause mass unsubscribes.
  • Broken Unsubscribe Links: Broken unsubscribe links frustrate users.
  • Change of Sending habits: Changes in sending frequency causes unsubscribes.

Key considerations

  • Review Security Software: Investigate whether organization-level security software is triggering unsubscribes.
  • Monitor Bot Activity: Implement measures to detect and mitigate bot activity.
  • List Hygiene Practices: Clean your email list regularly to remove inactive subscribers.
  • Segmentation & Content: Segment your audience and tailor content to their preferences. Align your new content with their original expectations.
  • Compliance: Ensure compliance with GDPR and other privacy regulations.
  • Sender Reputation: Monitor and maintain a good sender reputation.
  • Link Verification: Verify that all links, especially unsubscribe links, are working correctly.
  • Sending Frequency: Carefully examine your sending frequency, and don't suddenly increase it. Inform subscribers of any big changes.
Marketer view

Email marketer from Neil Patel Digital shares that poor list hygiene and old/stale email addresses can lead to mass unsubscribes. Regularly clean your list of inactive users.

December 2023 - Neil Patel Digital
Marketer view

Email marketer from Reddit suggests a possible explanation is that a spam filter or security software at the organization level might be automatically unsubscribing multiple users as a protective measure if it detects suspicious email activity.

February 2025 - Reddit
Marketer view

Email marketer from Email On Acid answers that bot activity might be responsible. Some bots automatically click links, including unsubscribe links, shortly after receiving an email.

January 2024 - Email On Acid
Marketer view

Email marketer from StackOverflow responds that broken links or errors on your unsubscribe page might cause frustration, leading users to unsubscribe as a last resort. Verify links are always working.

April 2021 - StackOverflow
Marketer view

Email marketer from Litmus explains that organizations use aggressive spam filters that automatically unsubscribe their users to protect their employees.

November 2021 - Litmus
Marketer view

Email marketer from Quora User answers that changes in sending frequency or the type of content you are sending might trigger unsubscribes if it doesn't align with what subscribers initially signed up for. Monitor your audience to understand preferences.

June 2024 - Quora
Marketer view

Email marketer from Sendinblue explains that a sudden drop in sender reputation could lead to more emails being marked as spam, triggering mass unsubscribes. Monitor your sender reputation regularly.

August 2024 - Sendinblue
Marketer view

Email marketer from Campaign Monitor answers that Irrelevant content or sending too many emails can prompt subscribers to unsubscribe en masse. Segment your lists to send relevant content to the right people.

December 2022 - Campaign Monitor
Marketer view

Email marketer from HubSpot responds that not adhering to GDPR and other privacy regulations can lead to subscribers unsubscribing. Ensure you have proper consent and clear unsubscribe options.

January 2023 - HubSpot

What the experts say
3Expert opinions

Multiple subscribers unsubscribing at the same time can be caused by one-click unsubscribe headers being triggered by filters checking all links in an email. This is especially likely if the implementation does not strictly follow the RFC 8058 protocol. A sudden increase in complaints or feedback loop reports can also trigger automated responses from mailbox providers, potentially blocking or rate-limiting emails, leading to simultaneous unsubscribes.

Key opinions

  • One-Click Unsubscribe Headers: List-unsub headers with one-click unsubscribe can be triggered by filters.
  • RFC 8058 Protocol: Improper implementation of RFC 8058 leads to unintended unsubscribes.
  • Complaint Spike: Sudden spike in complaints/feedback loops causes automated responses.

Key considerations

  • Review One-Click Implementation: Check implementation of one-click unsubscribe headers.
  • Adhere to RFC 8058: Ensure compliance with RFC 8058 protocol.
  • Monitor Feedback Loops: Regularly monitor feedback loops and complaint rates.
Expert view

Expert from Email Geeks recommends fixing the one-click unsubscribe implementation if it's not following the RFC 8058 protocol.

October 2021 - Email Geeks
Expert view

Expert from Word to the Wise explains that a sudden spike in complaints or feedback loop reports can trigger an automated response from some mailbox providers, leading to a block or rate limiting that might cause a simultaneous reaction across multiple subscribers.

October 2022 - Word to the Wise
Expert view

Expert from Email Geeks suggests that if a list-unsub header implements a one-click unsubscribe, it's likely a filter is checking all the links in the email.

January 2024 - Email Geeks

What the documentation says
4Technical articles

Multiple subscribers unsubscribing simultaneously can be triggered by a few automated actions. Security software might unintentionally trigger one-click unsubscribe headers if the implementation does not adhere to RFC specifications. Mailchimp purges unengaged subscribers. Gmail's spam filters automatically unsubscribe users who rarely open emails or mark them as spam. Microsoft's Safe Links feature can preemptively visit URLs, triggering unintended unsubscribes.

Key findings

  • Security Software: Security software can unintentionally trigger one-click unsubscribes.
  • Mailchimp Automation: Mailchimp purges unengaged subscribers.
  • Gmail Spam Filters: Gmail's spam filters automatically unsubscribe users.
  • Microsoft Safe Links: Microsoft's Safe Links can trigger unintended unsubscribes.

Key considerations

  • Review One-Click Implementation: Carefully review the implementation of one-click unsubscribe headers to ensure RFC compliance.
  • Engagement Strategy: Implement strategies to improve subscriber engagement to avoid being purged by platforms like Mailchimp.
  • Content Relevance: Ensure your emails are relevant and engaging to avoid being marked as spam.
  • Safe Links Settings: Check organization settings for Microsoft Safe Links to prevent false positives.
Technical article

Documentation from Google Support indicates that Gmail's spam filters can automatically unsubscribe users from emails they rarely open or mark as spam.

March 2022 - Google Support
Technical article

Documentation from Mailchimp Knowledge Base shares that unengaged subscribers will often be purged. Mailchimp uses automation to keep lists fresh and engagement up. This might also be a reason why you're losing subscribers, especially if they were not engaging.

November 2021 - Mailchimp Knowledge Base
Technical article

Documentation from Microsoft explains that Microsoft's Safe Links feature in Outlook can pre-emptively visit URLs in emails, which might trigger one-click unsubscribe links, resulting in unexpected unsubscribes. Check your organisations settings to avoid false positives.

June 2022 - Microsoft
Technical article

Documentation from ietf.org explains that List-Unsubscribe header with a one-click unsubscribe may be unintentionally triggered by security software, especially if the implementation doesn't strictly adhere to the RFC specifications.

July 2023 - ietf.org