Glossary Deliverability
What is email bounce rate? A safe threshold
Bounce rate is the percentage of sent emails that come back as undeliverable, usually because the address does not exist or the receiving server refused the message.
Bounce rate is bounced emails divided by emails sent. Hard bounces (the address does not exist) matter most; soft bounces (a full mailbox, a temporary error) may succeed on a later try.
There is no single published provider rule, but a common rule of thumb for cold email is to stay under about 2 to 3%. Higher rates tell providers you are sending to a poor list.
Why it matters
- High bounce rates are a strong spam signal to mailbox providers.
- Bounces usually mean old or guessed data, so they predict other problems with the list.
- Every bounce is a person you meant to reach and did not.
How Reach Crew handles it
Checker confirms each work address two ways before Writer drafts anything, so few emails bounce. If more than 3% of a mailbox's emails bounce once it has sent 50, or three bounce before that, Reach Crew pauses the mailbox and tells you. An address that bounced is never picked again for that person.
Related terms
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