Summary
Third-party email validation tools can assist in improving email hygiene and reducing hard bounces in B2B email deployments, but their effectiveness is limited and should not be solely relied upon. Experts recommend understanding the specific reasons for bounces by analyzing SMTP error codes and consulting with the ESP, as various factors beyond invalid addresses can cause delivery failures, including domain blocking, spam filters, and recipient engagement. Implementing proper list management, permission-based sending, actively monitoring bounce rates and engagement metrics, segmenting lists, and possibly utilizing human verification are essential practices to complement validation tools and achieve optimal deliverability.
Key findings
- Limited Accuracy: Email validation tools offer varying levels of accuracy and cannot guarantee 100% accuracy due to factors like catch-all servers and dynamic email configurations.
- Data Access: The effectiveness of validation tools depends on the data they have access to, which can become outdated over time.
- ESP Insights: The ESP knows the most about mail delivery and the specific reasons for bounces.
- Multiple Failure Causes: Email delivery can fail for many reasons beyond invalid addresses, including permission, relevance, and blocking.
- 5xx Errors are Permanent: 5xx SMTP error codes signify permanent failures and require immediate removal from the list.
Key considerations
- Combine with Best Practices: Integrate validation tools with double opt-in, regular list cleaning, and segmentation for improved deliverability.
- Monitor Engagement: Focus on engagement metrics and remove unengaged subscribers to enhance deliverability.
- Human Verification: Consider human verification, especially for B2B data, to ensure accuracy.
- Analyze Bounce Codes: Thoroughly analyze SMTP error codes to understand bounce reasons and differentiate between hard and soft bounces.
- Prioritize Permission: Emphasize permission-based sending and maintain accurate and up-to-date recipient lists.
What email marketers say
9 marketer opinions
Third-party email validation tools can assist in reducing hard bounces in B2B email deployments, but they are not foolproof. Their accuracy varies, and they should not be solely relied upon. Factors like catch-all servers, temporary addresses, dynamic email nature, and data access limitations impact their effectiveness. A combination of validation tools, robust list hygiene practices, permission-based sending, segmentation, engagement monitoring, and human verification are essential for optimal deliverability.
Key opinions
- Varying Accuracy: Third-party email validation tools offer differing levels of accuracy and cannot guarantee 100% accuracy.
- Data Limitations: The trustworthiness of validation tools diminishes over time as data becomes outdated or inaccurate.
- Catch-All and Role-Based Accounts: Validation tools may struggle to accurately identify catch-all and role-based accounts, leading to false positives.
- Not a Replacement: Email validation is not a replacement for permission-based sending and a strategic approach to email marketing.
Key considerations
- Combine with Best Practices: Use validation tools in conjunction with other practices like double opt-in, regular list cleaning, and segmentation.
- Monitor Engagement: Focus on engagement metrics and remove unengaged subscribers to improve deliverability.
- Human Verification: Consider human verification, especially for B2B data, to ensure accuracy.
- Data Hygiene: Regularly update email lists.
Marketer view
Email marketer from NeverBounce Blog explains that third-party email validation tools offer varying levels of accuracy. While they can identify invalid addresses, catch-all servers and temporary addresses may still pass validation, leading to potential bounces.
12 Dec 2022 - NeverBounce Blog
Marketer view
Email marketer from LeadGenius Blog responds that validation tools can help flag potentially problematic addresses, but human verification is often needed, especially for B2B data. They also suggest that regularly updating the list and prioritizing engagement are critical.
19 Jul 2021 - LeadGenius Blog
What the experts say
7 expert opinions
While third-party email validation tools can assist with email hygiene, experts caution that their effectiveness is limited and they should not be considered a complete solution for managing hard bounces in B2B email deployments. ESPs possess the most accurate information about delivery failures, and understanding the specific reason for a bounce is crucial before resending. Many factors beyond invalid addresses can cause delivery issues, including domain blocking, spam filters, and recipient engagement. Therefore, proper list management, permission-based sending, and monitoring actual bounce rates are essential complements to validation tools.
Key opinions
- Limited Scope: Validation tools only verify the existence of an email address and cannot guarantee deliverability or recipient interest.
- ESP as Best Source: The ESP provides the most reliable information regarding delivery failures.
- Catch-All Domains: Many B2B domains use catch-all addresses, leading to false positives with simple verification methods.
- Multiple Failure Reasons: Email delivery can fail for various reasons beyond invalid addresses.
Key considerations
- Understand Bounce Reasons: Before resending, investigate the specific SMTP bounce reason provided by the ESP.
- Monitor Bounce Rates: Validate the results of validation services by monitoring actual bounce rates.
- Prioritize Permission: Emphasize permission-based sending practices over relying solely on validation tools.
- Manage Lists Actively: Implement proper list management and hygiene practices.
Expert view
Expert from Word to the Wise answers that email validation services can only verify if an email address exists; they cannot guarantee deliverability or indicate if the recipient wants to receive emails. Atkins emphasizes the importance of permission and engagement-based sending practices over relying solely on validation tools.
1 Jun 2023 - Word to the Wise
Expert view
Expert from Email Geeks shares that many B2B domains use "catchall" addresses, leading to false positives in simple SMTP verification. Blocking during sending could indicate spam issues, not just unknown user problems.
16 Sep 2023 - Email Geeks
What the documentation says
4 technical articles
Email deliverability hinges on understanding and managing bounces effectively. Analyzing SMTP error codes helps distinguish between permanent (hard) and temporary (soft) bounces. Permanent failures, indicated by 5xx codes, necessitate immediate removal of the email address. Robust bounce handling, including suppression of hard bounces and implementing feedback loops, is critical for maintaining a positive sender reputation and complying with ISP requirements. Accurate and well-maintained recipient lists, alongside good content and IP management, are essential components of overall email deliverability.
Key findings
- SMTP Error Codes: SMTP error codes are critical for distinguishing between hard and soft bounces.
- 5xx = Permanent Failure: 5xx SMTP error codes indicate permanent failures and necessitate immediate removal from the mailing list.
- Bounce Handling: Proper bounce handling is crucial for maintaining sender reputation.
Key considerations
- Analyze Error Codes: Carefully analyze SMTP error codes to understand the reasons for bounces.
- Suppress Hard Bounces: Record and suppress hard bounces to prevent future delivery attempts.
- Implement Feedback Loops: Utilize feedback loops to monitor bounce rates and comply with ISP requirements.
- List Accuracy: Maintain accurate and current recipient lists.
Technical article
Documentation from Microsoft explains that improving deliverability of email is a multi-faceted process requiring good email content and a strategy for keeping sending IPs off of any block lists. Maintaining recipient lists current and accurate is a key component.
4 Aug 2021 - Microsoft Documentation
Technical article
Documentation from RFC Editor specifies that 5xx SMTP error codes indicate permanent failures. These should be treated as hard bounces, and the email address should be removed from the mailing list.
26 Dec 2021 - RFC Editor
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