Summary
Managing hard and soft bounces effectively is crucial for maintaining a healthy email list, good sender reputation, and ultimately, email deliverability. The best practices involve immediately removing hard bounces due to their permanent failure status and carefully monitoring soft bounces, which represent temporary issues. A key aspect is understanding bounce classifications, including eSMTP codes and variations across ISPs, to make informed decisions. A multifaceted approach includes regular list cleaning, engagement-based segmentation, re-engagement campaigns, and feedback loops to monitor complaints. Avoiding arbitrary rules and ensuring proper bounce processing with correct interpretation of bounce codes are also crucial.
Key findings
- Hard Bounce Removal: Hard bounces should be immediately removed from the email list to protect sender reputation and prevent deliverability issues.
- Soft Bounce Monitoring: Soft bounces should be monitored; addresses with persistent soft bounces should be suppressed, segmented, or targeted with re-engagement campaigns.
- List Hygiene: Regular list cleaning is essential for removing inactive or invalid email addresses, improving deliverability and sender reputation.
- Bounce Classification: Understanding bounce classifications, including eSMTP codes and ISP variations, is crucial for informed decision-making.
- Engagement Segmentation: Segmenting lists based on engagement improves deliverability by sending more frequently to active users.
- Proper Bounce Processing: Proper bounce processing, including accurate interpretation of bounce codes, is integral to running an effective email campaign.
Key considerations
- Mailbox Full: Consider abandoned mailboxes (full for an extended period) as candidates for hard bounce treatment.
- Arbitrary Rules: Avoid setting arbitrary rules for bounce management; carefully examine bounce reasons to identify specific issues.
- Bounce Code Interpretation: Be aware of potential misinterpretations of bounce codes due to substring searches and varying interpretations by ISPs.
- Rule Adjustment: Adjust bounce rules based on campaign frequency, business needs, and continuous monitoring of bounce rates as a key performance indicator.
- Feedback Loops: Implement feedback loops to monitor complaints and improve list hygiene.
- eSMTP Codes: Consider how to handle receivers that don't return eSMTP codes and how bounce classifications vary by ISP.
- Re-engagement Campaigns: Use re-engagement campaigns to confirm subscriptions and reactivate soft bouncers before suppression.
What email marketers say
12 marketer opinions
Managing hard and soft bounces effectively is crucial for maintaining a healthy email list and a good sender reputation. Experts recommend immediately removing hard bounces to prevent deliverability issues. Soft bounces should be monitored, and addresses with persistent soft bounces should be either suppressed or moved to a less frequent send segment. Regular list cleaning, engagement-based segmentation, and re-engagement campaigns are also valuable strategies. Furthermore, understanding bounce codes and not relying on arbitrary rules can help to maintain email deliverability.
Key opinions
- Hard Bounce Removal: Hard bounces should be immediately removed from the email list to protect sender reputation.
- Soft Bounce Monitoring: Soft bounces should be monitored, and persistent soft bouncers should be suppressed or segmented.
- List Hygiene: Regular list cleaning is essential for removing inactive or invalid email addresses.
- Engagement Segmentation: Segmenting lists based on engagement can improve deliverability by sending more frequently to active users.
- Re-engagement Campaigns: Re-engagement campaigns can help re-activate soft bouncers and confirm subscriptions.
- Bounce Code Understanding: Properly understand what the bounce codes mean instead of arbitrarily assigning rules to avoid misinterpretations.
Key considerations
- Mailbox Full: Consider an abandoned mailbox as a hard bounce after a period of time.
- Arbitrary Rules: Avoid setting arbitrary rules for bounce management without understanding the specific reasons for bounces.
- Bounce Code Interpretation: Be aware of potential misinterpretations of bounce codes due to substring searches and varying interpretations by ISPs.
- Rule Adjustment: Adjust bounce rules based on campaign frequency and specific business needs.
- Alerts and KPIs: Monitor bounce rates as a key performance indicator (KPI) and set up alerts for exceeding thresholds.
- Feedback Loops: Implement feedback loops to monitor complaints and improve list hygiene.
Marketer view
Email marketer from Digital Marketer shares that for soft bounces, a re-engagement campaign could be the solution. This would aim to have the recipent engage to resubscribe and acknowledge their subscription.
14 Feb 2022 - Digital Marketer
Marketer view
Email marketer from Mailjet emphasizes the importance of removing hard bounces immediately from the mailing list to protect sender reputation and improve deliverability. They also suggest monitoring soft bounces and suppressing them if they persist over time.
24 May 2025 - Mailjet
What the experts say
4 expert opinions
Effective bounce management is critical for email deliverability, focusing on understanding bounce classifications and processing them correctly. Experts emphasize that knowing why an email bounced (hard or soft) and how different ISPs report bounces is crucial for informed decision-making. Neglecting proper bounce management can harm list hygiene, sender reputation, and ultimately lead to deliverability issues.
Key opinions
- Classification Importance: Understanding bounce classifications is essential for determining how to handle future emails to an address.
- Bounce Processing Impact: Proper bounce processing is integral to email campaign performance; poor processing hurts deliverability.
- List Hygiene: Effective bounce management is critical for maintaining list hygiene and sender reputation.
Key considerations
- eSMTP Codes: Consider how to handle receivers that don't return eSMTP codes.
- ISP Variation: Be aware that bounce classifications can vary by ISP.
- Careful Handling of Soft Bounces: Handle soft bounces with care, balancing temporary issues and potential deliverability impacts.
Expert view
Expert from Email Geeks emphasizes that understanding how bounces are classified is crucial for determining how to handle future mail to that address, as the reason for the failure is important for making informed decisions.
26 Jun 2023 - Email Geeks
Expert view
Expert from Word to the Wise explains that effective bounce management is critical for maintaining list hygiene and sender reputation. It involves immediate removal of hard bounces and careful handling of soft bounces, as neglecting this aspect can lead to deliverability issues and blacklisting.
25 Dec 2022 - Word to the Wise
What the documentation says
3 technical articles
Email deliverability hinges on effectively managing hard and soft bounces. Documentation from SparkPost, Amazon SES, and Mailchimp consistently advises the immediate removal of email addresses causing hard bounces due to their permanent failure status. While soft bounces are temporary, monitoring and planning for their reduction are crucial, as excessive soft bounces can negatively impact sender reputation.
Key findings
- Hard Bounce Removal: Hard bounces represent permanent delivery failures and should be immediately removed from mailing lists.
- Soft Bounce Monitoring: Soft bounces indicate temporary issues and require monitoring to assess if they resolve over time.
- Reputation Impact: Excessive soft bounces can negatively impact sender reputation and overall email deliverability.
Key considerations
- Reduction Plan: Develop a plan to reduce the number of soft bounces to maintain a positive sender reputation.
- Automated Handling: Leverage platforms with automated bounce handling features, like Mailchimp, to streamline the process.
Technical article
Documentation from Mailchimp describes hard bounces as permanent delivery failures which you should immediately clean from your list, and soft bounces as temporary issues. Mailchimp automatically handles bounces in their email campaigns.
20 Oct 2022 - Mailchimp
Technical article
Documentation from Amazon SES states that you should immediately remove email addresses from your mailing list when they cause a hard bounce. Monitor soft bounces and have a plan to reduce the number of soft bounces that you send to. Too many soft bounces can negatively impact your sender reputation.
25 Jan 2025 - Amazon SES
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 should different bounce types be classified and handled by ESPs?
How should email marketers handle permanent bounce errors like full or inactive mailboxes?
