Email bounce rate is the share of sent messages that could not be delivered.
Category
Deliverability, Metrics
Also known as
email bounce rate; bounce
Hard bounces are permanent, such as an address that doesn't exist. Soft bounces are temporary, such as a full inbox. Mailbox providers read a high hard-bounce rate as a sign of a bought or stale list.
In practice
Suppress hard-bounced addresses automatically, and look into any send that bounces more than usual. A spike that comes from one import is a bad source file, not a deliverability problem.
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