Summary
Analyzing bounce data is critical for maintaining email list health, improving deliverability, and protecting sender reputation. Experts and marketers emphasize the need for detailed bounce information beyond simple 'hard' and 'soft' classifications. This includes unedited SMTP responses, sending IP, DKIM algorithms, and DSN data. Understanding SMTP error codes, ISP bounce policies, and the distinction between bounces and deferrals is crucial. Key strategies involve hard bounce removal, soft bounce segmentation, feedback loop setup, spam trap identification, and list validation. Automated bounce processing and comprehensive NDR reports are also valuable tools. Ultimately, detailed and actionable bounce data empowers email marketers to troubleshoot issues, optimize sending practices, and ensure sustainable deliverability.
Key findings
- Detailed Data Needed: Actionable bounce insights require detailed information such as SMTP responses, sending IPs, DKIM, DSN, and not just hard/soft categorizations.
- ESP Limitations: Current ESP classifications of bounces can be oversimplified and disconnected from reality.
- Value of Raw Codes: While raw codes offer detailed information, they can be overwhelming for some users.
- SMTP Codes and Standards: Understanding SMTP error codes and standards helps in diagnosing delivery issues.
- List Hygiene: Regularly removing hard bounces improves deliverability and sender reputation.
- Proactive Monitoring: Monitoring bounce rates and analyzing bounce data proactively identifies potential problems.
- ISPs Bounce Polices: Understanding the ISP bounce polices allows tailoring email practices to meet their requirements, reducing bounce rates and improving deliverability.
Key considerations
- Choosing an ESP: Select an ESP that provides detailed and actionable bounce data or actively manages delivery errors.
- Data Accessibility: Balance the need for detailed data with user-friendly interpretations.
- Automated Systems: Implement automated systems for bounce processing and suppression list management.
- Segmented Strategies: Develop strategies for segmenting soft bounces to improve engagement.
- Feedback Loops: Setup feedback loops to proactively identify and remove spam traps.
- Validation Services: Consider using list validation services to minimize bounces before sending.
What email marketers say
19 marketer opinions
Analyzing bounce data is crucial for maintaining email list health, improving deliverability, and safeguarding sender reputation. Email marketers emphasize the need for detailed bounce information, including unedited SMTP responses, sending IP, and DKIM algorithms, as well as monitoring DSN data and managing delivery errors. While raw bounce codes can be useful, ESPs often provide simplified interpretations. Key strategies include hard bounce removal, soft bounce segmentation, feedback loop setup, spam trap identification, list validation, and adherence to ISP bounce policies. Proper bounce management indicates a competent ESP and promotes sustainable email marketing practices.
Key opinions
- Detailed Bounce Data: Access to detailed bounce information (e.g., SMTP responses, sending IP, DKIM algo) enables precise problem diagnosis.
- ESPs and Bounce Management: Competent ESPs actively manage delivery errors and ideally provide actionable DSN data insights.
- Bounce Analysis is Essential: Analyzing bounce codes identifies underlying issues affecting email deliverability.
- Hard Bounce Removal: Removing hard bounces from email lists is essential for improving sender reputation and deliverability.
- Feedback Loops: Setting up feedback loops with ISPs helps identify and remove spam traps from email lists.
- Impact of High Bounce Rate: High bounce rates negatively impact sender reputation and deliverability.
Key considerations
- Raw vs. Simplified Codes: Balancing the need for detailed bounce data with the usability of simplified interpretations for non-technical users is key.
- Soft Bounce Management: Implementing strategies to manage soft bounces, such as segmentation and reduced sending frequency, is crucial.
- List Validation: Employing email list validation services prior to sending minimizes bounces from invalid addresses.
- ISP Policies: Understanding and adhering to specific ISP bounce policies improves deliverability.
- Monitoring Required: Regularly monitoring bounce rates and cleaning email lists is crucial for maintaining a healthy email program.
- DSN Data: A team needs to pour over DSN data to help clients become better senders by getting ahead of issues and are experienced in seeing certain patterns.
Marketer view
Email marketer from Reddit explains that setting up feedback loops with major ISPs provides valuable bounce data for identifying and removing spam traps from your email list.
12 May 2022 - Reddit
Marketer view
Email marketer from Litmus shares that regularly analyzing bounce data and removing hard bounces from your list improves deliverability and sender reputation.
1 Jul 2024 - Litmus
What the experts say
8 expert opinions
Experts emphasize the need for more useful and accurate bounce data from ESPs, as current 'hard' and 'soft' categorizations are often inadequate. Actionable data includes specific error details, the sending domain/MTA, and relevant technical information. Understanding SMTP error codes and bounce message formats is also essential for diagnosing deliverability problems and differentiating between temporary and permanent failures. The goal is to provide email marketers with the information necessary to troubleshoot and improve email deliverability.
Key opinions
- Inadequate ESP Bounce Data: Current 'hard' and 'soft' bounce categories from ESPs often lack accuracy and utility.
- Need for Detailed Information: Actionable bounce data requires specific error details, sending domain/MTA, and technical information.
- Importance of Standards: Understanding SMTP error codes and bounce message formats aids in diagnosing deliverability issues.
Key considerations
- ESPs Need Improvement: ESPs should prioritize providing more useful and accurate bounce data to email marketers.
- Focus on Actionability: Bounce data should be presented in a way that enables email marketers to troubleshoot and improve deliverability.
- Bounce definitions: Email marketers need to interpret the ESP bounce definitions carefully as they often don't represent reality
Expert view
Expert from Email Geeks responds that ESP bounce definitions have ZERO connection with reality.
6 May 2023 - Email Geeks
Expert view
Expert from Email Geeks explains that if she had a magic wand, she’d make ESPs actually give us useful bounce data, not just ‘hard’ and ‘soft’.
30 Dec 2023 - Email Geeks
What the documentation says
5 technical articles
Documentation highlights the importance of understanding different types of bounces and delivery failures for effective email marketing. Hard bounces signify permanent delivery failures (e.g., invalid address), while soft bounces indicate temporary issues (e.g., full inbox). Enhanced SMTP status codes and Non-Delivery Reports (NDRs) offer detailed diagnostic information. Automated bounce processing via SNS notifications facilitates real-time identification of bounced addresses and suppression list management. Differentiating between bounces and deferrals provides insights into delivery patterns and helps optimize sending strategies.
Key findings
- Hard vs. Soft Bounces: Hard bounces represent permanent delivery failures, while soft bounces indicate temporary issues.
- Enhanced Status Codes: SMTP Enhanced Status Codes provide more granular information for diagnosing delivery problems.
- Automated Bounce Processing: Automated bounce processing enables real-time identification of bounced addresses.
- NDR Reports: Non-Delivery Reports (NDRs) offer detailed information about delivery failures.
- Bounces vs. Deferrals: Understanding the difference between bounces and deferrals helps in analyzing delivery patterns.
Key considerations
- List Hygiene: Regularly remove hard bounces to maintain list health and sender reputation.
- Error Code Analysis: Leverage enhanced status codes and NDR reports for in-depth troubleshooting.
- Automated Systems: Implement automated systems for efficient bounce processing and suppression list management.
- Delivery Pattern Analysis: Monitor both bounces and deferrals to identify and address delivery challenges proactively.
Technical article
Documentation from SparkPost clarifies the distinction: bounces are permanent failures, while deferrals are temporary delivery delays which may eventually resolve. Monitoring both helps understand delivery patterns.
18 Sep 2022 - SparkPost
Technical article
Documentation from Microsoft explains that Non-Delivery Reports (NDRs) provide detailed information about why an email could not be delivered, including the specific error code and a description of the problem.
10 Jan 2025 - Microsoft Support
Can a hard bounced email address become deliverable again, and under what circumstances?
Can 'invalid recipient' bounce messages be false positives and what should I do about it?
Do soft bounces affect email deliverability and sender reputation?
How are email bounce rates calculated and what is considered a good bounce rate?
How do I troubleshoot email bounce messages?
How long should emails be kept in a bounce email inbox?
