Summary
The collected advice presents a nuanced view on emailing 'unknown' status users after email validation during transactional domain warming. While some experts suggest proceeding cautiously by segmenting these users and closely monitoring bounces, a stronger consensus leans towards avoiding sending to 'unknown' addresses altogether, particularly during the critical domain warming phase. The rationale is rooted in minimizing potential damage to sender reputation, reducing the risk of being categorized as sending Graymail, avoiding spam traps and maintaining a clean list, ultimately improving overall deliverability. Technical documentation underscores the importance of adhering to email infrastructure standards and prioritizing engaged, opted-in users.
Key findings
- Reputation at Risk: Emailing 'unknown' addresses poses a risk to sender reputation and overall deliverability.
- Validation Uncertainty: 'Unknown' status signifies uncertainty in email address validity due to limitations in validation tools or data availability.
- Segmentation as Mitigation: Segmenting 'unknown' users and sending to them later, if at all, can mitigate potential negative impacts.
- List Hygiene Priority: Maintaining a clean email list by removing unengaged and potentially invalid addresses is paramount.
- Bounce Rate Sensitivity: Keeping bounce rates low (ideally below 3%) is crucial for positive sender reputation.
- Graymail Concerns: Sending to unengaged or unknown users will increase the chance that your email will be categorized as Graymail, which should be avoided for transactional emails.
Key considerations
- Domain Warming Strategy: During domain warming, prioritize sending to known-good addresses to establish a positive reputation from the outset.
- ESP Metrics Understanding: Thoroughly understand how your ESP calculates deliverability and interprets different delivery statuses.
- Validation Tool Nuances: Recognize the limitations and specific meanings of validation statuses provided by your chosen tool.
- Risk-Benefit Assessment: Weigh the potential benefits of reaching 'unknown' users against the considerable risks to deliverability and reputation.
- Compliance with Standards: Adhere to SMTP standards and bulk sender guidelines to ensure optimal email delivery.
- Opt-in Practices: Emphasize opt-in practices and user engagement to build a healthy and responsive email list.
- Monitor Graymail: Monitor where your mail is landing and make sure you are taking action to avoid being classified as Graymail.
What email marketers say
10 marketer opinions
The consensus among email marketers is to exercise caution when emailing users with an 'unknown' status after email validation, especially during transactional domain warming. Sending to these addresses carries potential risks to sender reputation and deliverability. Strategies range from segmenting and testing small batches to outright removal, with the underlying goal of minimizing bounces, spam complaints, and maintaining a healthy sender score.
Key opinions
- Reputation Risk: Emailing 'unknown' status users can harm your sender reputation and deliverability.
- Validation Variance: Email validation tools vary in their ability to assess email address validity, and an 'unknown' status often indicates uncertainty.
- Segmentation Strategy: Segmentation of 'unknown' addresses for low-priority sending is a common recommendation.
- Cautious Approach: A cautious approach, including removing or suppressing 'unknown' addresses, is generally favored, particularly during domain warming.
Key considerations
- Validation Tool Accuracy: Understand the limitations of your email validation tool and the meaning of 'unknown' status in its context.
- Testing Strategy: If considering emailing 'unknown' addresses, conduct small-scale testing to assess bounce rates and potential issues.
- Segmentation Implementation: Implement a clear segmentation strategy for 'unknown' addresses to minimize potential negative impacts on overall deliverability.
- Long-Term Impact: Weigh the potential short-term gains of emailing 'unknown' addresses against the potential long-term damage to sender reputation.
- Domain Warming: During domain warming, prioritize sending to the highest quality addresses to establish a positive reputation.
Marketer view
Email marketer from StackExchange explains that 'unknown' status often means the validation service couldn't confirm deliverability. They suggest sending a small test batch to see if the addresses bounce before including them in larger sends.
19 Oct 2024 - StackExchange
Marketer view
Email marketer from Reddit shares that when in doubt, it’s best to err on the side of caution. They recommend segmenting or removing ‘unknown’ addresses, especially during domain warming, to avoid potential issues with mailbox providers.
28 Mar 2022 - Reddit
What the experts say
7 expert opinions
Experts offer varied perspectives on handling 'unknown' status users after email validation. Some suggest continuing to mail while monitoring bounces, particularly if the 'unknown' status stems from a lack of data. Segmenting these users and sending to them last during a warmup process is recommended to mitigate potential deliverability issues. Maintaining list hygiene by removing unengaged users is crucial, and avoiding high bounce rates remains a key objective. Sending to 'unknown' users can lead to Graymail categorization which is undesirable.
Key opinions
- Unknown Status Ambiguity: 'Unknown' status may indicate a lack of data or an inability to verify the email address, not necessarily invalidity.
- Segmentation Mitigation: Segmenting 'unknown' users and sending to them later in the warmup process minimizes potential damage.
- Bounce Rate Importance: Maintaining a low bounce rate (below 3%) is crucial for email deliverability.
- List Hygiene Impact: List hygiene, including removing unengaged users, significantly affects deliverability.
- Graymail Impact: Sending to unengaged or unknown users can cause your emails to be categorized as Graymail, especially your important transactional emails.
Key considerations
- ESP Deliverability Metrics: Understand how your ESP calculates deliverability rate and the meaning of 'sent' vs. 'delivered' statuses.
- Validation Tool Interpretation: Interpret validation tool statuses correctly; 'unknown' may not equal 'invalid'.
- Warming Strategy: Prioritize sending to known good addresses during domain warming, delaying sends to 'unknown' users.
- Bounced Monitoring: Monitor bounce rates and remove hard bounces promptly.
- Graymail Avoidance: Avoid sending to unknown users to avoid having your mail categorized as Graymail.
Expert view
Expert from Word to the Wise explains that list hygiene is a part of maintaining your email deliverability. It is important to remove unknown users or unengaged users to maintain your email marketing success.
29 Aug 2023 - Word to the Wise
Expert view
Expert from Email Geeks explains that an “Unknown” status from a hygiene service likely means the service doesn’t have data or can’t check the email address. He suggests to keep mailing and handle bounces.
15 Jul 2021 - Email Geeks
What the documentation says
4 technical articles
Technical documentation emphasizes maintaining a clean and engaged email list, though it doesn't directly address 'unknown' statuses. These resources offer insights into email infrastructure, bounce handling, and sender guidelines, highlighting the importance of sending to valid users and the difficulties in definitively validating every email address, which can result in 'unknown' classifications.
Key findings
- Clean List Importance: Maintaining a clean email list is crucial for deliverability.
- Engaged User Priority: Sending emails to engaged users is vital to avoid deliverability issues.
- Infrastructure Insights: Understanding email infrastructure and delivery responses helps interpret validation results.
- Validation Limitations: Definitively validating every email address is not always possible.
Key considerations
- RFC Compliance: Be aware of SMTP standards and how they influence email validation processes.
- Bounce Handling: Implement robust bounce handling mechanisms based on your ESP's guidelines.
- Sender Guidelines: Adhere to bulk sender guidelines, particularly those of major email providers like Google.
- Opt-in Best Practices: Prioritize sending to users who have explicitly opted in to receive your emails.
Technical article
Documentation from RFC 5321 outlines SMTP standards which indirectly relate to email validation. While it doesn't directly address 'unknown' statuses, it provides context on how mail servers communicate, and why some validation services might not be able to definitively determine the validity of an email address.
5 Jul 2021 - RFC 5321
Technical article
Documentation from Google's bulk sender guidelines recommends maintaining a clean email list and removing invalid addresses. Although it doesn't directly address 'unknown' statuses, it highlights the importance of sending emails to valid and engaged users to avoid deliverability issues when sending to Gmail users.
21 Nov 2022 - Google Bulk Sender Guidelines
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