What is the best way to clean an email list with steadily decreasing open rates?

9 Marketer opinions 3 Expert opinions 5 Technical articles 3 Resources

Summary

Cleaning an email list with steadily decreasing open rates requires a comprehensive strategy involving multiple tactics. A core element is identifying and removing unengaged subscribers (typically inactive for 3-12 months), along with invalid addresses and unsubscribes, to maintain good list hygiene and improve deliverability. Re-engagement campaigns should be used to attempt to revive interest before removal. Implementing double opt-in from the start and validating email addresses at signup helps prevent low engagement. It's also vital to address the root cause of declining open rates, considering content relevance, audience expectations, and general list hygiene practices. Segmentation, suppression lists, and sunset policies are valuable tools. Remember, fixed audiences naturally decline, so continuous subscriber acquisition is essential.

Key findings

Engagement-Based Segmentation: Segmenting lists based on engagement allows for targeted re-engagement campaigns and more relevant content.
Inactive Subscriber Removal: Removing unengaged subscribers (3-12 months) significantly improves deliverability and sender reputation.
Double Opt-in: Using double opt-in prevents low engagement by ensuring subscribers genuinely want to receive emails.
Email Validation: Validating email addresses upon signup prevents deliverability issues and reduces bounce rates.
Root Cause Analysis: Declining open rates may stem from issues beyond list hygiene, such as irrelevant content or unmet audience expectations.
Audience Decay: Fixed email audiences naturally decline over time, requiring continuous acquisition of new subscribers.
Sender Reputation: Maintaining a clean list is essential for preserving a positive sender reputation, impacting deliverability.
Suppression Lists: Using suppression lists ensures that you don't email known complainers, unsubscribes, or spam traps.

Key considerations

Relevance and Expectations: Ensure email content is relevant and meets the expectations of your subscribers to maintain engagement.
Sunset Policy: Implement a sunset policy to gracefully remove unengaged subscribers, giving them one last chance to interact.
Subscriber Acquisition: Prioritize consistent efforts to acquire new, engaged subscribers to offset natural audience attrition.
Frequency of Cleaning: Establish a regular schedule for cleaning your email list to maintain optimal deliverability.
Reconfirmation Campaigns: Consider running reconfirmation campaigns to ensure subscribers still want to receive your emails.

What email marketers say
9Marketer opinions

Cleaning an email list with steadily decreasing open rates involves a multi-faceted approach. Strategies include running re-engagement campaigns, removing unengaged subscribers (those who haven't opened or clicked in 3-12 months), implementing double opt-in, and validating email addresses at signup. It's also important to look at the root cause of declining open rates, such as content relevance and recipient expectations. Segmentation and targeted re-engagement efforts are recommended before removing subscribers. Utilizing a suppression list and sunset policies are also effective practices.

Key opinions

Re-engagement Campaigns: Sending targeted re-engagement campaigns to inactive subscribers can help revive interest.
Subscriber Removal: Removing unengaged subscribers (3-12 months inactivity) improves deliverability.
Double Opt-in: Using a double opt-in process prevents low engagement from the start.
Email Validation: Validating email addresses upon signup prevents issues later on.
Root Cause Analysis: Declining open rates may be due to content relevance or recipient expectations, not just list hygiene.
Segmentation: Segmenting lists based on engagement and sending targeted emails enhances relevance.
Suppression Lists: Using suppression lists helps avoid sending to known complainers or unsubscribes.

Key considerations

Content Relevance: Ensure your email content meets recipient expectations to maintain engagement.
Sunset Policies: Implement a sunset policy to gradually decrease email frequency before removing unengaged subscribers.
Confirmed Opt-in: Consider implementing a Confirmed Opt-in or reconfirmation campaign.
Root Cause: Look at the root cause of the problem and address issues with content or list hygiene methods.

Marketer view

Email marketer from StackOverflow responds that validating email addresses upon signup prevents issues later on. They also use a suppression list to avoid sending to known complainers or unsubscribes.

June 2024 - StackOverflow

Marketer view

Marketer from Email Geeks suggests that if you've been steadily mailing the list, then hygiene is unlikely to be your issue and you should look to see if you're meeting recipient expectations.

August 2021 - Email Geeks

Marketer view

Marketer from Email Geeks suggests that a reconfirmation campaign via Confirmed Opt-In is what you need when cleaning an email list.

August 2024 - Email Geeks

Marketer view

Email marketer from OptinMonster responds that using a double opt-in process from the start can help prevent low engagement. They also recommend regularly cleaning your list by removing bounced emails, unsubscribes, and inactives.

August 2022 - OptinMonster

Marketer view

Marketer from Email Geeks shares that if your open rate is steadily dropping, then you may need to look at the root cause. Sure, it could be a statistical issue with too many non-engaged recipients, but it could also be related to your content or general list hygiene methods.

June 2024 - Email Geeks

Marketer view

Email marketer from Mailjet explains that removing unengaged subscribers is crucial. They recommend identifying and removing subscribers who haven't opened or clicked emails in the past 3-6 months to improve deliverability.

May 2022 - Mailjet

Marketer view

Email marketer from Sendinblue shares that segmenting your list and sending targeted re-engagement campaigns to inactive subscribers is a good start. If they still don't engage, it's best to remove them.

May 2024 - Sendinblue

Marketer view

Email marketer from Quora suggests segmenting your list based on engagement and sending targeted emails to different segments. Focus on re-engaging your inactive subscribers with special offers or exclusive content.

October 2023 - Quora

Marketer view

Email marketer from Reddit explains that they periodically send a 'last chance' email to inactive subscribers, offering them a reason to stay subscribed. Those that don't respond are removed.

April 2024 - Reddit

What the experts say
3Expert opinions

Maintaining a clean email list with declining open rates involves understanding that audience decay is natural and proactively managing subscriber engagement. Key strategies include focusing on engagement-based segmentation, removing inactive subscribers (typically those unengaged for 6-12 months), implementing sunset policies to gradually reduce email frequency before removal, and continuously adding new subscribers to counteract audience attrition.

Key opinions

Audience Decay: Fixed audiences naturally decline over time if new subscribers aren't added.
Engagement-Based Segmentation: Segmenting based on engagement allows for targeted strategies for different user groups.
Inactive Subscriber Removal: Removing subscribers who haven't opened or clicked in 6-12 months improves deliverability.
Sunset Policies: Gradually decreasing email frequency to unengaged subscribers before removal minimizes negative impact.

Key considerations

Subscriber Acquisition: Continuously acquire new subscribers to offset natural audience decay.
Engagement Definition: Define what constitutes 'engagement' for your audience to determine inactivity thresholds.
Sunset Policy Implementation: Design a clear and gradual sunset policy to provide opportunities for re-engagement.
Deliverability Impact: Understand how removing inactive subscribers positively impacts your overall email deliverability.

Expert view

Expert from Spam Resource shares that a key method is to implement a sunset policy, where you gradually decrease the frequency of emails to unengaged subscribers before ultimately removing them. This provides an opportunity for re-engagement while minimizing negative impact on deliverability.

June 2021 - Spam Resource

Expert view

Expert from Word to the Wise explains that it's important to focus on engagement-based segmentation and removal. They suggest identifying subscribers who haven't opened or clicked in a significant period (e.g., 6-12 months) and removing them from active sending.

November 2022 - Word to the Wise

Expert view

Expert from Email Geeks explains all fixed audiences will decline over time. If you aren't adding new, it's like a pond with no incoming flow of water - over time it will dry out.

October 2021 - Email Geeks

What the documentation says
5Technical articles

Maintaining a clean email list with steadily decreasing open rates is crucial for preserving a positive sender reputation and ensuring deliverability. Key actions involve removing invalid email addresses (hard bounces), unsubscribes, and users who haven't engaged for a period of time. Sending unwanted mail negatively impacts domain reputation and can lead to emails being marked as spam. Regularly suppressing unengaged subscribers and providing easy unsubscribe options are also important practices to avoid spam traps and maintain list hygiene.

Key findings

Domain Reputation: Consistently sending unwanted mail harms domain reputation and leads to spam flagging.
Invalid Address Removal: Removing hard bounces is critical for protecting sender reputation.
Unsubscribe Options: Providing easy unsubscribe options is essential for compliance and user experience.
Engagement Matters: Sending only to engaged users improves deliverability.
Inactive Removal: Regularly removing inactive addresses improves sender reputation.

Key considerations

List Hygiene: Prioritize consistent list hygiene practices to maintain a healthy email program.
Sender Reputation: Understand the importance of sender reputation and how list cleaning impacts it.
Compliance: Adhere to email marketing regulations and best practices for user consent and opt-out options.
Spam Traps: Regularly clean your list to avoid hitting spam traps.

Technical article

Documentation from Validity (formerly ReturnPath) shares that maintaining list hygiene is essential for good deliverability. They recommend regularly removing invalid email addresses and suppressing unengaged subscribers to improve your sender reputation and avoid spam traps.

February 2025 - Validity

Technical article

Documentation from Spamhaus explains that good list hygiene involves removing invalid email addresses, unsubscribes, and users who haven't engaged in a while. This helps maintain a good sender reputation and avoid being listed as a spam source.

December 2024 - Spamhaus

Technical article

Documentation from AWS explains that hard bounces indicate a permanent delivery failure, and you should immediately remove these addresses from your sending list to protect your sender reputation.

May 2024 - AWS

Technical article

Documentation from Google explains that consistently sending unwanted mail can harm your domain's reputation and cause email to be marked as spam. They recommend only sending to engaged users and providing easy unsubscribe options.

March 2023 - Google Support

Technical article

Documentation from Microsoft shares that maintaining a clean email list helps prevent being flagged as a spammer. They suggest regularly removing invalid or inactive email addresses to improve sender reputation.

October 2021 - Microsoft