Types of Email Bounces

Email bounces are categorized into two main types based on their cause:

• Soft Bounce:

  • A soft bounce occurs when an email is temporarily undeliverable to the recipient's mailbox. This could be due to reasons such as:

  • Mailbox Full: The recipient's mailbox is full and cannot accept new emails at the moment.
  • Temporary Server Issues: Issues like a server timeout or a temporary problem with the recipient's mail server.
  • Message Size Exceeds Limit: The email message is too large for the recipient's mailbox to accept.

  • Soft bounces are usually retried by the sender's email server for a certain period (often several days) before being classified as a hard bounce.

• Hard Bounce:

  • A hard bounce occurs when an email cannot be delivered permanently. This is typically due to:

  • Invalid Recipient Address: The email address does not exist or is misspelled.
  • Domain Name Does Not Exist: The domain part of the email address (e.g., example.com) does not exist.
  • Recipient Email Server Error: The recipient's mail server consistently rejects the email due to policy reasons or blacklist issues.

  • Hard bounces are typically not retried by the sender's email server and are considered permanent delivery failures.

Implications of Bounces

• Email Deliverability:

  • High bounce rates can negatively impact email deliverability. Internet Service Providers (ISPs) and email providers monitor bounce rates to gauge the sender's reputation. A high bounce rate can signal poor list hygiene or spammy sending practices.

• Sender Reputation:

  • Consistently sending emails that result in bounces, especially hard bounces, can damage a sender's reputation. ISPs may classify such senders as spammers, leading to emails being filtered or blocked.

• List Hygiene:

  • Managing bounce rates is crucial for maintaining a clean email list. Regularly removing hard bounced email addresses and addressing soft bounce issues can improve deliverability and sender reputation.

• User Engagement:

  • Bounces can indicate inactive or outdated email addresses on the mailing list. Cleaning up these addresses can improve engagement metrics such as open rates and click-through rates

Handling Bounces

• Monitoring and Reporting:

  • Email systems often provide bounce notifications or reports that indicate the type and reason for each bounce. These reports help administrators identify and address delivery issues promptly.

• List Management:

  • Implement practices to maintain list hygiene, such as removing email addresses that consistently bounce (especially hard bounces) and validating new email addresses before adding them to the list.

• Compliance and Best Practices:

  • Follow email marketing regulations (e.g., CAN-SPAM Act, GDPR) and best practices to minimize bounce rates and maintain sender reputation.