Catch-all emails: why most verifiers get them wrong
Catch-all addresses are the trickiest result in email verification. They're not clearly valid or invalid — and how you handle them affects both deliverability and how many real contacts you keep.
What catch-all means
A catch-all (accept-all) domain accepts mail for every possible address, so the receiving server says yes to anything. That makes it impossible to confirm from the outside whether a specific mailbox actually exists.
Why it's risky
Some catch-all addresses are real and deliverable; others don't exist and will eventually bounce or hit a trap. Treating them all as valid inflates risk; treating them all as invalid throws away real contacts.
How to handle them
- Send to catch-alls cautiously — start with engaged segments.
- Weight them lower in your quality score.
- Watch their engagement and prune the silent ones.
- Never assume a catch-all list is fully deliverable.
A better signal
BounceBlock flags catch-all addresses clearly and folds them into a per-list quality score, so you can make an informed call instead of guessing.