What is the Difference Between Bounced and Undeliverable Emails in ‘Activity by Email’ Reporting
When reviewing your Activity by Email report, you’ll notice metrics labeled Bounced and Undeliverable. While both relate to emails that failed to reach a recipient, they mean slightly different things — and knowing the difference can help you keep your lists clean and improve deliverability.
Bounced Emails
A Bounced email is one that was attempted to be delivered to the recipient, but the recipient’s email server returned it as undeliverable. This failure can occur for several reasons, including:
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The email address no longer exists or was never valid
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The recipient’s inbox is full
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The recipient’s server is not accepting messages at that time
When an email bounces, it is still technically sent — but it fails to reach the intended inbox. These bounce events get tracked in your reporting so you can see where delivery issues occur.
Undeliverable Emails
Undeliverable emails represent addresses that your mail server has already learned cannot be delivered to, usually because they have bounced in the past or are flagged in our internal suppression lists.
These emails are not sent again — the system recognizes from previous delivery attempts that they are unlikely to be accepted, so it won’t try to send the email to those addresses again.
Over time, as more emails bounce, they may be automatically classified as Undeliverable to help protect your sender reputation and improve deliverability.
📊 How These Metrics Work Together
| Metric | What It Means |
|---|---|
| Bounced | Email was sent but rejected or returned |
| Undeliverable | Email was not sent because it cannot be delivered based on past information |
Tracking both metrics helps you understand current delivery attempts (Bounced) versus known failing addresses (Undeliverable).
💡 Best Practices
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Review your bounced addresses and remove or update invalid contacts.
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Periodically clean your email lists to reduce future undeliverables.
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Watch your email engagement trends in the Activity by Email report to improve list quality.
If you have questions about a specific report or deliverability issue, contact the Support Team for help.