What’s the ideal suppression timing (immediate vs delayed)?

Suppression timing depends on bounce type:

Immediate suppression (hard bounces):

User does not exist: Suppress now. Domain invalid: Suppress now. Permanent rejection: Suppress now. No benefit to waiting; address is definitively invalid.

Delayed suppression (soft bounces):

Mailbox full: May clear in hours or days. Server busy: Retry likely to succeed. Greylisting: Second attempt usually works. Threshold approach protects against premature suppression.

Threshold recommendations:

3-5 consecutive soft bounces. Over 7-30 day window. Consider bounce type in threshold.

Why timing matters:

Too fast: Loses valid addresses on temporary issues. Too slow: Damages reputation by repeated failures.

Right timing balances subscriber preservation with reputation protection. Hard = immediate; soft = measured patience.