Catch-All Email Verifier: Confirm Some, Flag the Rest

What a catch-all email verifier does

A catch-all domain accepts mail for any address, real or made up. That means the usual mailbox check proves little: the domain says yes to everything, so a yes doesn't tell you the person exists.

A catch-all email verifier tells you which of your addresses sit on such domains and, where it can, whether the mailbox is real. Catch-all verification is part of every CampaignKit check, so you don't run it separately. For what catch-all is and why companies set it up, read what is a catch-all email?

What we can and can't confirm

For some addresses on catch-all domains, CampaignKit gets a definite answer. Those come back as a normal valid result, with no catch-all flag, and you treat them like any other valid address.

For the rest, the address is flagged catch-all. That means the mailbox is unconfirmed, not bad: the domain accepts mail, but we can't tell whether this mailbox exists. No verifier can confirm every catch-all mailbox, so expect some of your catch-all addresses to stay flagged.

Keep two limits in mind. A valid result is a strong signal, not a promise of delivery. And some flagged addresses will bounce, which is why the next sections are about how you send to them.

How to verify catch-all emails with CampaignKit

Pick the route that matches how many addresses you have and where they live. Every route shows the catch-all result:

Route	Where the catch-all result shows	Start here
Free email verifier (one address, no account)	A Catch-All row in the result panel; 5 free checks an hour, no signup	Free email verifier
Bulk verification (a list you paste or upload as a file)	Catch-all addresses count as Deliverable and download with the rest unless you clear "Include catch-all addresses"	Bulk email verifier
API (your own app or signup form)	The result carries a catchAll flag in its description	API reference, developers
Zapier and n8n (no-code workflows)	A flag you can filter on: "Is Catch-All Domain" in Zapier, is_catchall in n8n	Zapier, n8n

If your addresses come in through forms, see real-time email verification for checking them at signup. If you're preparing a whole list for a send, see email list cleaning.

What to do with catch-all results

Catch-all is unconfirmed, not invalid. Dropping every catch-all address can mean losing real contacts, so decide by where each address came from:

Where the address came from	What to do
Double opt-in signup	Send. The person confirmed the address.
Signup form without confirmation	Send to a small test batch first, then watch bounces and engagement.
Purchased or scraped list	Suppress, or confirm the person another way before you send.
High-value B2B prospect	Check a second source first, then send in a small batch.

Then work through three steps:

1. Segment. Keep catch-all addresses in their own list, so you can watch their bounces and engagement apart from the rest.
2. Send in small batches. Start with 50 to 100 addresses, check bounces and complaints after each batch, and pause if they rise.
3. Suppress non-engagers. Drop addresses that don't engage after two sends, and any address that complains.

The full version, with the risks of sending to catch-all addresses, is in our guide to catch-all emails and whether to send to them.

What a catch-all result looks like

In a bulk job, the summary counts catch-all addresses under Deliverable, and the download includes them unless you clear "Include catch-all addresses". In the API, a catch-all address usually comes back as valid with a catchAll flag in its description. The free email verifier shows it in the Catch-All row. Catch-all is its own flag, so an address can also be flagged disposable or role at the same time.

Catch-all email verification pricing

You start with 200 free validations and no credit card. Each validated address uses one credit, and a catch-all address is one credit like any other. After the free validations you buy credits in packs: there's no subscription, and credits never expire.

Pack size	Price	Cost per 1,000 emails
2,500 emails	$6	$2.40
10,000 emails	$15	$1.50
50,000 emails	$75	$1.50
100,000 emails	$120	$1.20
1,000,000 emails	$429	$0.43

See every pack on the pricing page. Verifying more than 1,000,000 emails? Contact sales for custom pricing.

Related

• What is a catch-all email, and should you send to it?
• The bulk email verifier for files and pasted lists.
• Email list cleaning before a campaign.
• Real-time email verification for signup, checkout and lead forms.
• The free email verifier for a single address.
• The developers page and the email validation API reference.
• Pricing, security and the data processing agreement.