The interplay between spam traps, user engagement, and list cleaning practices is critical for maintaining strong Gmail deliverability. While some mistakenly believe engagement is the sole metric Google considers, the presence of spam traps and an unhygienic list can significantly degrade your sender reputation, ultimately impacting inbox placement.
Key findings
Holistic approach: Gmail's filtering algorithm utilizes a combination of metrics, not solely engagement. Technical issues like high bounce rates or frequent spam trap hits contribute to poor deliverability.
Spam traps' impact: Hitting spam traps, especially recycled ones, can lead to your IP or domain being added to blocklists (or blacklists), severely affecting your sender reputation and increasing the likelihood of emails landing in the spam folder. Understanding how spam traps work is essential.
Inactive subscribers: Recycled spam traps originate from email addresses that have become inactive and were later repurposed by ISPs. Continuing to email these addresses indicates poor list hygiene.
List hygiene importance: Regularly cleaning your email list by removing unengaged or inactive subscribers is a foundational step for improving deliverability and sender reputation (including your Google email reputation). This proactive approach is more effective than solely relying on engagement metrics after the fact.
Key considerations
Proactive cleaning: Do not wait for deliverability issues to arise before performing list hygiene. Regular maintenance is crucial to prevent issues. The Email on Acid blog on list cleaning provides further insights on this.
Defining inactivity: Establish a clear policy for inactive subscribers, typically removing those who haven't engaged in 6-12 months. This includes subscribers who never opened an email after signing up.
Engagement measurement: Focus on positive engagement metrics like opens, clicks, and replies to guide your sending strategy and identify truly active subscribers.
Verification vs. cleaning: While email verification services can help identify invalid addresses at the point of subscription, they are not a substitute for ongoing list hygiene that removes unengaged users who might become recycled spam traps.
What email marketers say
Email marketers often face a balancing act between maximizing reach and maintaining list hygiene. There's a common misconception that major inbox providers like Gmail focus exclusively on engagement metrics, leading some to downplay the importance of proactively cleaning their lists. However, seasoned marketers emphasize that neglecting list quality can have severe consequences, including blocklistings and diminished sender reputation, regardless of perceived overall campaign engagement.
Key opinions
List health matters: A dirty list, characterized by high bounce rates and frequent spam trap hits, will inevitably lead to emails going to spam, regardless of other positive engagement signals.
Recycled traps: Sending to segments of inactive subscribers (e.g., those who haven't opened in 12 months) carries the risk of hitting recycled spam traps, which directly harms sender reputation and deliverability.
Engagement is not everything: While engagement is crucial, it doesn't negate the negative impact of fundamental list quality issues. Spam traps are a symptom of poor list management.
Proactive removal: It is better to remove unresponsive subscribers proactively rather than cling to the hope that they 'might' respond, as their continued presence can damage your overall sending health.
Key considerations
Defining inactivity timeframe: While conversion to a spam trap can vary (6 to 18 months), a 6-month inactivity window is a good starting point for identifying subscribers to remove or re-engage.
New subscriber vigilance: Even newly acquired addresses can be spam traps if they were invalid from the start. Monitoring opens from the beginning is important.
List validation utility: List validation services can be useful for initial clean-ups or at the point of subscription, especially if not using double opt-in, to ensure format correctness and validity. However, they are not a complete solution for ongoing list health; regular engagement-based culling is also required. Our article on email validation services discusses this further.
Re-engagement campaigns: Consider special campaigns to re-engage inactive subscribers, but if they don't respond, remove them to protect your sending reputation. This is part of managing inactive subscribers.
Marketer view
Email marketer from Email Geeks warns that a dirty list with many spam trap hits and bounces will inevitably lead to emails landing in the spam folder, even if engagement is otherwise high. It's fundamental to start with a clean foundation.
10 Feb 2020 - Email Geeks
Marketer view
Email marketer from Email Geeks emphasizes that hitting recycled spam traps will result in blocklisting. They advise either ceasing emails to old contacts or using a reliable list cleaner to maintain a healthy sender reputation.
10 Feb 2020 - Email Geeks
What the experts say
Experts in email deliverability consistently highlight that while user engagement is a strong signal for Gmail, it does not operate in isolation. Spam traps and poor list hygiene are fundamental issues that undermine any positive engagement metrics. They emphasize that deliverability is a multi-faceted problem requiring a comprehensive approach, where cleaning your list is a critical, foundational step rather than an optional add-on.
Key opinions
Combination of factors: Gmail uses every available metric to train its filters. While engagement is key, spam traps and other list quality indicators are also crucial in determining inbox placement.
Spam traps as symptoms: Hitting spam traps signifies a deeper issue with list health, particularly that you are emailing individuals who have been inactive for an extended period, leading to a 'sick' list.
ROI and engagement: Removing unresponsive addresses improves not only engagement rates but also the return on investment (ROI) of your email campaigns, as you're only sending to engaged recipients.
No sharing of traps: Reputable blocklists (or blacklists) do not share their spam trap lists, as this would undermine their purpose. Claims by list vendors to work with DNSBLs to identify traps are often misleading.
Key considerations
Address underlying issues: Instead of focusing solely on removing spam traps as a quick fix, address the root cause, which is often poor list acquisition or retention practices.
Long-term strategy: While list cleaning provides an immediate boost, consistent good sending practices, including ongoing list hygiene and consent-based acquisition, are essential for sustained deliverability. Read more about how email list quality impacts deliverability.
Verification limitations: Email validation services can help remove obvious bad addresses, but they cannot guarantee the removal of all spam traps or fully address the problem of disengaged subscribers. This relates to how to identify email spam traps.
One-click unsubscribe: While offering clear unsubscribe options is generally good for email filters, certain implementations of one-click unsubscribe can be problematic if automated anti-spam systems click these links inadvertently.
Expert view
Deliverability expert from Email Geeks states that Google explicitly does not trust or rely on spam traps. This perspective suggests that while list hygiene is important, the impact of spam traps specifically on Google's filtering might be overstated by some.
10 Feb 2020 - Email Geeks
Expert view
Deliverability expert from Email Geeks asserts that mail is not blocked or junked solely because of spam traps. They suggest that using the 'threat' of spam traps can be a tool to encourage clients to adopt better sending practices, which will yield significant benefits.
10 Feb 2020 - Email Geeks
What the documentation says
Official documentation from major mailbox providers like Gmail clearly outlines sender guidelines that prioritize responsible email practices. While they may not explicitly detail the exact weight of every factor, the overarching message emphasizes sending wanted, relevant mail. This inherently includes managing list quality, as sending to invalid or disengaged recipients is contrary to delivering valued content.
Key findings
Sender responsibility: Gmail's guidelines are designed to ensure messages are delivered to the inbox by promoting responsible sending behavior. This encompasses all aspects of your email program, from authentication to content and list quality.
User intent: Mailbox providers primarily aim to deliver mail that users genuinely want to receive. This means prioritizing engagement and ensuring your emails are relevant to the recipient.
List hygiene implicitly supported: Although spam traps may not be explicitly mentioned as a primary blocking factor by Google, the emphasis on sending to engaged users and minimizing complaints implicitly demands a clean, permission-based list.
Reputation factors: Sender reputation (including IP and domain reputation) is built on a variety of signals, including bounce rates, spam complaints, and user engagement, all of which are negatively impacted by a dirty list.
Key considerations
Adherence to guidelines: Routinely review and adhere to the latest Gmail sender guidelines to ensure compliance and optimal deliverability.
Permission-based lists: Build email lists primarily through explicit, permission-based opt-ins to ensure recipients genuinely want your emails, minimizing the risk of spam complaints and hitting traps. Our guide to avoiding spam traps outlines effective strategies.
Consistent monitoring: Regularly monitor your deliverability metrics and sender reputation through tools like Google Postmaster Tools. This allows you to quickly identify and address any declines. You can learn more in our ultimate guide to Google Postmaster Tools V2.
Engagement strategy: Develop strategies to keep subscribers engaged and remove those who consistently show no interaction to prevent them from becoming deliverability liabilities.
Technical article
Google documentation on preventing mail from being blocked or sent to spam states that the guidelines provided help ensure your messages are delivered to Gmail's inbox. They suggest using the tips to reduce issues, emphasizing responsible sending.
10 Feb 2020 - Google Help
Technical article
The Klaviyo blog on Gmail & Outlook deliverability best practices highlights that maintaining list hygiene is crucial for keeping your negative engagement rate low. They reiterate that a clean list is a key general best practice.