Summary
Deciding when to remove unengaged subscribers is a critical aspect of maintaining a healthy email list and ensuring optimal email deliverability. While there's no universal 'magic number', the consensus among deliverability experts and marketers leans towards proactive management rather than simply letting dormant contacts accumulate. This practice (often called list hygiene or list scrubbing) directly impacts your sender reputation, reduces costs, and improves the accuracy of your email marketing analytics.
Key findings
- Sender reputation is paramount: Internet Service Providers (ISPs) closely monitor how recipients interact with your emails. Sending consistently to unengaged subscribers can signal to ISPs that your content is irrelevant or unwanted, leading to lower inbox placement or even having your domain or IP address added to a blocklist.
- Spam trap risk: Old, inactive email addresses can be converted into spam traps. Hitting these traps significantly damages your sender reputation and can lead to being blacklisted. Understanding what spam traps are is essential.
- Re-engagement first: Before outright removal, a strategic re-engagement campaign is often recommended. This gives subscribers a chance to confirm their interest and helps identify those who are truly disengaged.
- Varying timelines: The optimal removal timeframe depends heavily on your business model, sales cycle, and content frequency. A daily sender might consider a shorter period (e.g., 3-6 months) while a quarterly newsletter might allow for longer inactivity (e.g., 9-12 months or more).
Key considerations
- Define engagement: Clearly define what constitutes engagement for your specific context (e.g., opens, clicks, website visits, purchases). This will inform your unengagement criteria.
- Segment your list: Before removal, segment your unengaged subscribers into a separate list. This allows for targeted re-engagement efforts without affecting the deliverability of your active segments.
- Monitor deliverability metrics: Regularly check your email metrics, including open rates, click-through rates, and complaint rates. A decline in these metrics, especially without a significant change in sending volume or content, can be a sign of poor list hygiene. Further insights on this can be found in this article on why you should say goodbye to inactive subscribers.
- Data accuracy: Ensure your engagement data is accurate. Sometimes, technical issues (e.g., image blocking) can hide actual opens, or a user might still be engaging with your brand outside of email.
What email marketers say
Email marketers often face a balancing act between maintaining a large list size for perceived reach and ensuring high deliverability. The sentiment among marketers frequently highlights the challenge of convincing stakeholders that removing subscribers is beneficial, despite clear evidence that it improves sender reputation and overall marketing ROI. Practical approaches involve setting clear definitions of inactivity and implementing structured re-engagement paths.
Key opinions
- The '6-month' debate: Many marketers perceive a 6-month inactivity period as a critical point for aggressive sunsetting, though some acknowledge this can be overly aggressive for certain business models. It's often seen as a round number people are comfortable with.
- Overcoming traditional mindsets: It can be challenging to persuade individuals with older or print-centric marketing mindsets that a 6-month sunset milestone is realistic or beneficial, as they often prioritize list size.
- Impact on metrics: Removing unengaged contacts is seen as crucial for improving email deliverability, cutting costs associated with sending to dead leads, and gaining more accurate analytics on true audience engagement.
- Preventing negative feedback: Proactively removing unengaged subscribers prevents future unsubscribes and spam reports, which are detrimental to sender reputation.
Key considerations
- Tailor to sales cycle: The appropriate unengagement period should align with your typical customer sales cycle and purchase patterns, ensuring you don't remove potential future customers too soon.
- Re-engagement strategy: Always attempt to re-engage inactive subscribers through targeted campaigns before removal. Learn how to re-engage inactive subscribers effectively.
- Address stakeholder concerns: Prepare data and arguments to persuade management to prioritize list quality over raw list size. This is crucial for long-term deliverability and success, as highlighted by Klaviyo's email list hygiene best practices.
- Data acquisition: Be mindful that email addresses from alternative or older lists, even if not purchased, can sometimes contain spam traps if not properly maintained.
Marketer view
Marketer from Email Geeks questions how long a subscriber must be unengaged before directly scrubbing their email instead of attempting re-engagement. This highlights a common dilemma for email marketers.
Marketer view
Marketer from Email Geeks observes that a 6-month period of inactivity often appears as a critical point for aggressively sunsetting subscribers, based on discussions and readings within the industry.
What the experts say
From an expert perspective, the timeline for removing unengaged subscribers is highly nuanced, influenced by factors like the sender's business model and the sophisticated tactics ISPs use, such as dynamic spam traps. Experts often challenge commonly held beliefs about recycled spam traps and emphasize the importance of understanding the diverse origins of email list issues beyond just purchased data.
Key opinions
- Sales cycle dictates strategy: The optimal removal period depends fundamentally on an organization's sales cycle, typical customer behavior, and purchasing patterns, making a generic timeframe like 6 months often too aggressive.
- Recycled spam trap prevalence: Some experts assert that recycled spam traps are not widely used by major email service providers. The few entities that do employ them often season these domains for 1-2 years before converting them to traps.
- Dynamic traps: Microsoft, for example, has 'dynamic traps' where they temporarily accept mail to non-existent accounts to monitor suspicious traffic, even though these addresses should typically bounce. This differs from traditional recycled traps.
- RFC guidelines for traps: The spamtrap RFC (Request for Comments) suggests a minimum seasoning period of 12 months for domains before they are used as spam traps.
Key considerations
- Understanding trap types: Differentiate between various types of spam traps (e.g., pure, recycled, dynamic) to implement the most effective list hygiene practices.
- Beyond data purchases: Spam traps don't only originate from purchased data; they can also result from typographical errors by subscribers or other organic list growth issues.
- Accurate bounce management: It's crucial to properly handle bounces, particularly hard bounces, as these often indicate invalid or defunct addresses that could become traps. Reviewing your bounce data is an important step in managing bad email addresses.
- Long-term list health: Prioritize long-term list health over short-term list size. Sending to a smaller, more engaged audience consistently yields better deliverability and campaign performance, as outlined by Spamresource.com.
Expert view
Expert from Email Geeks advises that the decision of when to remove unengaged subscribers is highly dependent on an organization's sales cycle, the typical behavior of its customers, and established purchase patterns.
Expert view
Expert from Email Geeks comments that a 6-month inactivity period for list cleansing is a 'nice round number' that many people find comfortable, perhaps due to its simplicity rather than its universal applicability.
What the documentation says
Official documentation and research consistently underscore the critical link between list hygiene and email deliverability. They often define what constitutes unengagement and provide best practices for managing subscriber lists to avoid negative impacts on sender reputation. The emphasis is on maintaining a high-quality list rather than merely a large one, in alignment with the filtering criteria of major Mailbox Providers (MBPs).
Key findings
- Quality over quantity: Documentation frequently advises that a smaller, engaged list will always outperform a large list filled with unengaged or invalid contacts. This directly impacts deliverability and sender reputation.
- Engagement as a ranking factor: ISPs like Gmail and Yahoo explicitly use engagement metrics (opens, clicks, replies, spam complaints, unsubscribes) as significant factors in determining inbox placement. Low engagement leads to emails being filtered to spam.
- Lifecycle management: Official guides often recommend lifecycle stages for subscribers, including re-engagement flows for inactive users and eventual sunsetting if engagement isn't restored.
- Prevention of negative signals: Removing unengaged contacts proactively helps prevent accumulation of spam complaints and hard bounces, which are strong negative signals to ISPs and can lead to being added to a blocklist or blacklist.
Key considerations
- Regular audits: Perform regular audits of your email list to identify and segment inactive users. This routine maintenance is fundamental to preventing email deliverability issues.
- Re-engagement campaigns: Design specific re-engagement campaigns that aim to rekindle interest. If these fail, then proceed with removal. Learn how to manage deliverability during re-engagement.
- Subscription changes: Offer options for subscribers to change their frequency or content preferences, rather than forcing them to unsubscribe entirely. This can reduce inactivity and improve engagement.
- ISP-specific guidance: Pay close attention to postmaster guidelines from major ISPs like Google and Yahoo, as their policies heavily influence the impact of unengaged subscribers.
Technical article
Deliverability documentation from Mailgun.com outlines various reasons and triggers for when disengaged users should be removed from an email list, including factors like abuse or spam complaints.
Technical article
Documentation from Klaviyo Help Center states that by proactively removing unengaged contacts, senders can prevent future unsubscribes and spam reports, which are both damaging to sender reputation.
Related resources
6 resources
Related pages
How can managing inactive email subscribers improve Gmail deliverability?
How to re-engage inactive email subscribers and when should you stop sending?
How do Internet Service Providers track email engagement and its impact on deliverability?
How to manage deliverability when re-engaging inactive email subscribers?
How does email list quality and sending frequency impact deliverability and sender reputation?
What is the best way to remove bad email addresses from a list?
How to re-engage stale email subscribers after deliverability issues?
What are good email engagement thresholds for deliverability monitoring?
Spam traps: what they are and how they work
What are the different types of spam traps and how do they work?
