A normal verification usually answers in a few seconds. Catch-all resolution does more work for each address, so it usually takes several seconds and can occasionally take up to a minute.
Why it's slower
A regular check asks the mail server one question. On a catch-all domain that question has no useful answer, so resolution has to work harder for each mailbox, and it has to wait for the receiving side to respond. Some mail systems answer quickly; others are slow or busy, and we wait rather than guess.
The time depends on the domain, not on your account or plan. Addresses at the same domain usually take about the same time.
What this means in practice
Single checks
After you press Resolve catch-all, the button shows Resolving… until the answer arrives. Keep the page open; if you close it, the result won't be shown, and you can resolve again later.
Bulk jobs
Resolution runs in the background. Results appear in the table as each address finishes, so you can start working with the first ones while the rest continue. You can close the page and come back.
A large batch of catch-all rows takes longer than the first verification pass. For a first look, resolve a sample (select a few rows and press Resolve catch-alls), then run the rest.
Email finder
With Resolve catch-all domains ticked, a lookup on a catch-all domain takes longer than one on a normal domain, because the email is confirmed before it's returned. Lookups on normal domains are not slowed down.
If you call filtrat from another tool
Tools that call filtrat for each row, such as Clay, n8n or your own code, must wait long enough for a resolution to finish:
| Setting | Recommended |
|---|---|
| Response timeout | 90 seconds |
| Retries | 2 |
A short timeout makes rows fail even though the resolution would have succeeded. In Clay, the default timeout is far too low; see Recommended column settings.
For many rows at once, use a bulk job instead of row-by-row calls: start it, then read the results when it's done. See Long-running jobs.
Waiting longer never costs more. You're charged 5 only when an address comes back deliverable or invalid, however long it took.