Hard Bounces vs Soft Bounces
Hard bounces: Invalid email addresses — permanently undeliverable. PostMTA suppresses these automatically within hours.
Soft bounces: Temporary failures (mailbox full, server down). PostMTA retries 72 hours then suppresses if still failing.
PostMTA Bounce Processing Features
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Instant suppression — Hard bounces suppressed immediately
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Bounce classification — Identifies mailbox full vs domain no longer exists
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Feedback loop integration — FBL from major providers (Gmail, Microsoft)
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List hygiene scoring — Scores subscribers by engagement
Best Practices
- Verify emails at signup (API check before adding to list)
- Remove addresses that soft-bounce 3+ times
- Monitor your sender score at postmta.com/dashboard
- Use dedicated IPs for different list segments
PostMTA handles bounces automatically →