Summary
The collective insights from marketers, experts, and ESP documentation emphasize a robust approach to bounce management. The consensus centers on classifying bounces as 'hard' or 'soft,' with hard bounces (permanent failures) mandating immediate removal from email lists to safeguard sender reputation. Soft bounces (temporary issues) warrant retries, followed by eventual suppression if unresolved. Automation by ESPs is vital for this process. While the hard/soft classification is dominant, some suggest a more nuanced 'remove from future mailings' approach. Maintaining a low bounce rate (under 2%) is crucial for deliverability. Proper list hygiene, reputation management, and tracking bounces are key considerations. Google's spam detection further highlights the importance of sending only to valid addresses. Furthermore it is essential to differentiate between temporary and permanent email delivery failures.
Key findings
- Bounce Classification: The primary classification is between 'hard' (permanent) and 'soft' (temporary) bounces.
- Hard Bounce Handling: Hard bounces necessitate immediate removal from email lists.
- Soft Bounce Handling: Soft bounces should be retried but eventually suppressed after a set period or number of attempts.
- Automation: ESPs should automate bounce processing and list management.
- Low Bounce Rate: Maintaining a low bounce rate (ideally below 2%) is critical for deliverability.
- Reputation Impact: High bounce rates negatively impact sender reputation.
- Alternate Approach: An alternate approach suggests a nuanced 'remove from future mailings' classification beyond strictly hard/soft.
- Google's Spam Detection: Google actively detects and prevents spam by monitoring sending patterns to invalid addresses.
- Differentiate Failures: It is essential to distinguish between temporary and permanent email delivery failures.
Key considerations
- List Hygiene: Maintain a clean email list by regularly removing hard bounces.
- Reputation Management: Implement proper bounce handling procedures to protect sender reputation.
- Automation Implementation: Effectively utilize ESP automation features for bounce management.
- Bounce Rate Monitoring: Consistently monitor bounce rates to identify and address deliverability issues.
- Soft Bounce Strategy: Define a clear strategy for handling soft bounces, including retry limits and eventual suppression.
- Address permanent failures: Prioritise addressing permanent failures
What email marketers say
11 marketer opinions
The provided responses converge on the importance of classifying email bounces, primarily into 'hard' and 'soft' categories, and implementing appropriate handling procedures. Hard bounces, representing permanent delivery failures, should be immediately removed from mailing lists to protect sender reputation. Soft bounces, indicating temporary issues, can be retried for a limited period before being treated as hard bounces. ESPs are expected to automate this process, and maintaining a low bounce rate (below 2%) is critical for email deliverability.
Key opinions
- Bounce Classification: Bounces are categorized into hard (permanent failure) and soft (temporary issue) bounces.
- Hard Bounce Handling: Hard bounces should be immediately removed from the mailing list.
- Soft Bounce Handling: Soft bounces can be retried, but eventually treated as hard bounces if the problem persists.
- Automation by ESPs: ESPs should automate bounce processing and list management.
- Bounce Rate Impact: High bounce rates negatively impact sender reputation and deliverability.
- Deliverability Threshold: A bounce rate below 2% is generally considered good for deliverability.
Key considerations
- List Hygiene: Maintaining a clean email list by promptly removing hard bounces is essential.
- Reputation Management: Proper bounce handling is crucial for protecting sender reputation and ensuring high deliverability.
- ESP Capabilities: Leverage ESPs' capabilities to automate bounce processing and list management.
- Monitoring and Analysis: Regularly monitor and analyze bounce rates to identify and address deliverability issues.
- Use of tools and methods: Tools such as Regex and ESP API's should be considered
Marketer view
Email marketer from MailerLite shares that ESPs should automatically process bounces, distinguishing between hard and soft bounces. Hard bounces should result in immediate removal from the subscriber list to protect sender reputation. Soft bounces can be retried for a limited time, after which they should be treated as hard bounces.
3 Oct 2022 - MailerLite
Marketer view
Marketer from Email Geeks explains that both bounces are "hard" bounces, and as an ESP, they would stop attempting to deliver messages to those addresses and advise customers to suppress them.
15 Aug 2022 - Email Geeks
What the experts say
3 expert opinions
Experts emphasize the importance of proper bounce handling for maintaining email list hygiene and sender reputation. They highlight the need to differentiate between temporary and permanent failures, suggesting immediate removal of addresses causing permanent bounces. One expert proposes a nuanced approach beyond strict hard/soft classifications, advocating for removing addresses from future mailings. Tracking bounces and deliverability is considered critical for effective email marketing.
Key opinions
- Differentiate Failures: It is essential to distinguish between temporary and permanent email delivery failures.
- Immediate Removal: Addresses with permanent failures should be immediately removed from the mailing list.
- Beyond Hard/Soft: Classifying bounces strictly as 'hard' or 'soft' may be insufficient; consider a more nuanced approach.
- Tracking Bounces: Tracking bounces and overall deliverability is critical for effective email marketing.
Key considerations
- List Hygiene: Prioritize maintaining a clean email list to safeguard sender reputation.
- Nuanced Classification: Consider alternative bounce classifications beyond traditional 'hard' and 'soft' categories.
- Deliverability Tracking: Implement robust bounce and deliverability tracking mechanisms.
- Proactive Management: Take proactive steps in bounce management to ensure email marketing success.
Expert view
Expert from SpamResource explains that when identifying and managing non-desirable addresses within an email list, it's essential to differentiate between temporary and permanent failures. Immediate removal of email addresses experiencing permanent failures is crucial for maintaining list hygiene and safeguarding sender reputation.
13 Oct 2022 - SpamResource
Expert view
Expert from Email Geeks suggests classifying the bounces as "remove the address from future mailings" instead of strictly "hard" or "soft", indicating the current bounce management system is flawed.
2 Jul 2022 - Email Geeks
What the documentation says
5 technical articles
Email service providers (ESPs) and email platforms (like AWS SES, Mailjet, SendGrid, Gmail) categorize email bounces primarily as 'hard' or 'soft.' Hard bounces signify permanent delivery failures, such as invalid email addresses, necessitating immediate removal from mailing lists. Soft bounces indicate temporary issues, like full mailboxes, and are typically retried before eventual suppression. Google and Gmail implement methods to reduce spam based on sending to many invalid emails. Delivery Status Notifications (DSNs) provide technical error codes and classifications.
Key findings
- Bounce Categories: Bounces are primarily classified as hard and soft by major ESPs.
- Hard Bounce Handling: Hard bounces result in immediate removal of email addresses from mailing lists.
- Soft Bounce Handling: Soft bounces are retried, but lead to eventual suppression if the problem persists.
- Spam Prevention: Gmail/Google Workspace uses methods to reduce spam based on sending to invalid addresses.
- DSNs: Delivery Status Notifications (DSNs) provide technical codes for delivery failures.
Key considerations
- List Hygiene: Regularly remove hard bounces to maintain a clean and healthy email list.
- Automated Suppression: Implement automated processes to handle bounce classification and suppression.
- Retry Strategies: Employ retry strategies for soft bounces within defined limits.
- Monitoring: Monitor bounce rates and address patterns of failures.
- DSN Usage: Utilize DSN codes for more advanced bounce diagnostics and handling logic
Technical article
Documentation from Mailjet explains that bounce types should be classified as either 'hard' or 'soft'. Mailjet automatically handles bounces, suppressing hard bounces to protect sender reputation. Soft bounces are retried a number of times before being considered a hard bounce.
25 May 2024 - Mailjet
Technical article
Documentation from RFC Editor provides technical details about Delivery Status Notifications (DSNs). It defines codes and classifications to specify the type of error/failure that occurred during email delivery.
14 Apr 2023 - RFC Editor
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 can I troubleshoot email bounce issues effectively in Email Geeks?
What are bounce message error codes and how should I interpret them?
