New Playbook: Cold Email Infrastructure Setup Guide
Read Now arrow_forwardA catch-all domain accepts mail to every address, real or invented, so no verifier can confirm a single mailbox on it. Mailsfinder returns those as their own segment with the reason attached, rather than calling them valid and letting you find out at bounce time.
Used by 1,000+ sales, recruiting and marketing teams
The same answer in the app, in a bulk file and in the API, so your code and your spreadsheet agree.
Paste an address and a catch-all domain comes back risky, with the catch-all flag set and the reason in plain words.
Try it in the app arrow_forwardUpload a list and catch-all addresses download as their own segment, separate from deliverable and undeliverable.
Upload a listPOST /email/verifyEmail returns Unknown for a catch-all rather than Valid, so your branch logic can route it.
View the API page arrow_forwardVerification works by asking the recipient mail server whether a mailbox exists. A catch-all server is configured to say yes to every name, so the answer carries no information about that specific person. Any tool reporting it as valid is reporting the server's politeness, not a fact.
We ask the server about an address that cannot exist at that domain.
If the server accepts that address, it accepts everything, and the domain is catch-all.
Risky in the app, Unknown in the API, with catch_all set to true in both.
Send in a watched batch, route to another channel, or suppress. The flag makes it a choice.
Three approaches that work, in the order most teams try them.
Send it separately
A smaller batch from a secondary domain, watched for bounces before anything bigger goes out.
Raise confidence first
Check the address against the company pattern and whether the person still works there. A matching pattern on a live employee is a better bet than a guess.
Use another channel
LinkedIn or a phone call for the names worth the effort, so an unconfirmable address does not cost you the account.
Large companies on Microsoft 365 are frequently catch-all, so a clean-looking enterprise list is often the least confirmable one you own.
Client lists arrive with the catch-all share already baked in. Reporting it up front stops the bounce conversation later.
University and hospital domains catch everything. A separate segment keeps a good candidate from being suppressed by mistake.
A catch-all flag on the record tells sales to confirm the address another way before a sequence starts.
Test any domain free, five a day with no signup, or start verifying lists with 100 free credits a day.
