What is the M3AAWG recommendation for bounce reporting?
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If you've ever wondered whether you're handling bounces the "right" way, M3AAWG (the Messaging, Malware and Mobile Anti-Abuse Working Group) has published clear guidance on this. They're the industry body that sets the benchmark for responsible sending practices, so their recommendations carry real weight with mailbox providers.
Here's the short version: process bounces fast, act on patterns, and treat rising bounce rates as a signal worth investigating rather than just a number to suppress your way out of.
Hard bounces: suppress immediately. A hard bounce means the address is permanently undeliverable. It could be a typo, a deleted account, or a domain that no longer exists. M3AAWG's position is clear here. Remove it from your active list right away. Continuing to send to hard-bounced addresses tells mailbox providers you're not paying attention, which chips away at your sender reputation fast.
Soft bounces: watch the pattern, not just the count. A soft bounce is a temporary failure (a full inbox, a server timeout, a brief outage). M3AAWG doesn't say suppress after one soft bounce. What they recommend is watching how a pattern develops over time. If an address is soft-bouncing consistently across multiple sends, that's a sign it's heading toward undeliverable. Most senders treat an address as a hard bounce candidate after 3 to 5 consecutive soft bounces, which aligns with M3AAWG's intent.
Rate monitoring matters just as much as suppression. M3AAWG flags bounce rate as a key indicator to track over time. A sudden spike usually points to a deliverability crisis, a compromised domain, or a data quality incident. A slow, steady climb over weeks is often a sign of list aging or a shift in how you're acquiring subscribers. Both patterns deserve investigation, not just cleanup.
The point M3AAWG keeps coming back to is this: high bounce rates are a symptom, not the disease. Suppressing bounced addresses is necessary, but if you don't ask why they happened, the underlying problem (poor acquisition, list age, data decay) will keep producing more of them. Check your retention practices for your bounce list too, since keeping that suppression list intact is what stops you from accidentally re-adding bad addresses later.
Not sure if your bounce rate is in a healthy range right now? Our SOS hotline is free and we'll take an honest look with you.
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