Soft Bounce
A temporary email delivery failure that may succeed on retry.
A soft bounce occurs when an email is temporarily undeliverable. Common causes include:
- Full mailbox: The recipient's inbox has reached its storage limit
- Server downtime: The recipient's mail server is temporarily unavailable
- Message too large: The email exceeds the server's size limit
- Rate limiting: The sending server has been temporarily throttled
- Greylisting: The server delays first-time senders as a spam prevention measure
Most email service providers will automatically retry soft bounces 3-5 times over 24-72 hours. If an email continues to soft bounce after multiple attempts, it should be treated as a hard bounce and removed from your list.
Related Terms
Bounce Rate
The percentage of emails that could not be delivered to the recipient's inbox.
Hard Bounce
A permanent email delivery failure caused by an invalid address, non-existent domain, or server rejection.
Greylisting
A spam prevention technique where a mail server temporarily rejects emails from unknown senders, expecting legitimate servers to retry.
Related Blog Posts
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