Bounce classification: hard, soft, and what to do about each

Not every bounce means the same thing. Treating them all alike is how senders quietly wreck their reputation.

Hard bounces

A hard bounce is a permanent failure, the mailbox does not exist, or the domain rejects you outright. Continuing to send to a hard-bounced address tells the receiver you are not maintaining your list. BookMySpot suppresses these automatically so you cannot hit them again by accident.

Soft bounces

Soft bounces are temporary, a full mailbox, a server that is briefly down, greylisting. These are retried on a backoff schedule. Only after repeated failures is an address escalated to suppression.

When to intervene

Most of this is automatic. You should step in when you see a sudden spike in hard bounces, which usually means a bad import or a list you should not be mailing, or when a specific provider starts deferring everything, which can signal a reputation problem worth investigating in Postmaster Tools.

Reading the suppression list

The suppression list is your record of who you must not contact. Review it periodically, but resist the urge to remove entries without a real reason, they are there to protect you.