Email quality checks and verification

Updated Markdown

ListPlus checks the quality of your email column two ways: free, instant pattern checks that run automatically on every list (see "What are the Analyze panel checks?" for the full picture), and an optional, paid deliverability check that actually asks a mail server whether an address is real. This topic covers both for email specifically, and explains what a "verified" result does and doesn't guarantee.

The free email checks#

ListPlus runs these checks on every row each time you open the Analyze panel, at no cost and with no setup. You'll see them there with the exact labels below:

  • Invalid Email Format — not a valid email at all (missing @, spaces, more than one @, no top-level domain).
  • Disposable Email Domain — a temporary/throwaway address (e.g. a 10-minute-mail service).
  • Role-Based Email — an address like info@, admin@ or support@ rather than a named person.
  • Personal Email Domain — a free consumer provider (Gmail, Yahoo, Outlook.com and similar) — informational, not an error.
  • Email Domain Typo — a likely typo in the domain (e.g. gmial.com), with a suggested fix you can apply.
  • Numeric-Heavy Email — a local part with excessive digits, often a scraped or system-generated address.
  • Test Domain Email — a development/test domain (e.g. example.com, herokuapp.com) rather than a real contact address.

A few more detailed checks also run but are less common: Consecutive Dots in Email, Email Local Part Too Long, Plus Addressing (like name+test@), Unusual Email Domain Ending, and Random Email Local Part. All of these look only at the text of the address — they never contact a mail server, so they cost nothing and run instantly, even on lists with tens of thousands of rows. Fixing what they find (accepting a typo suggestion, clearing a bad value) is covered in "Fixing issues from a check".

Verifying deliverability (the paid step)#

Format checks can't tell you whether an address actually exists. For that, open a row's Record panel or the list's Enrich panel (next to Analyze and Record in the list header) and use Verify Email Deliverability (in the Enrich panel it's under Verify). It checks each address against the mail server for its domain and costs 0.1 credit per email — but only when the answer is valid, invalid or disposable; a catch-all, unknown or error result is not charged. Results are cached for 7 days, so re-running verification on the same address within that window doesn't cost credits again.

After the check, the email cell is marked: red means the address is invalid, disposable or couldn't be checked; amber means the result was unclear (unknown). Valid and catch-all addresses stay unmarked. The results behind these colours are:

  • valid — the mail server confirmed the mailbox exists.
  • invalid — the mail server rejected the address; it doesn't exist.
  • catch-all — the domain accepts mail for any address at that domain, so the server can't confirm this specific mailbox exists or not (see below).
  • disposable — a temporary/throwaway domain (same signal as the free Disposable Email Domain check, confirmed at the mail-server level).
  • unknown — the mail server gave no clear answer (for example a timeout or greylisting). Treat it as unverified, not as bad.
  • error — the check failed. ListPlus marks the address red and skips it in later enrichments; run the verification again later.

Some addresses never reach the mail server at all: if the free checks already flag an address as invalid, disposable, a role account, a test domain, or a typo, ListPlus marks it right away, for free, without calling the mail server: format errors, role accounts like info@, test domains and typos are marked invalid, disposable domains disposable, and addresses with lots of digits unknown. Keep this in mind if you want to email a role account: it will show as invalid.

What "verified" does and doesn't guarantee#

A valid result means the mailbox existed and accepted mail at the moment of checking — it is a strong, real-time signal, not a promise. Mailboxes get deleted, fill up, or start rejecting mail after the fact, and no verification service — including this one — can guarantee that a message sent later won't bounce. Verifying your list before a send meaningfully reduces bounce risk; it does not eliminate it.

Catch-all domains#

A catch-all domain accepts any address, valid or not, so the verifier can't say whether one specific mailbox is real. Many companies run their mail this way on purpose. Treat a catch-all result as "unconfirmed, proceed with normal caution" rather than as an error — it is not the same as invalid. In the list, a catch-all address isn't highlighted, so it looks like a valid one. It is still unconfirmed.

See "What are the Analyze panel checks?" for how checks work across all data types, "Fixing issues from a check" for applying suggested fixes, "What every action costs" for the full credit table, and "Duplicates" for merging repeated contacts.

FAQ#

What free email checks does ListPlus run automatically?#

Invalid Email Format, Disposable Email Domain, Role-Based Email, Personal Email Domain, Email Domain Typo, Numeric-Heavy Email and Test Domain Email — all pattern-based and free, and they run automatically every time you open the Analyze panel.

What counts as an invalid email format?#

Missing the @ symbol, having more than one @, containing a space, or missing a top-level domain (like .com) after the @. ListPlus flags these instantly with the Invalid Email Format check — no mail server is contacted.

What is a disposable email address?#

An address from a temporary or throwaway email service (the kind used to sign up once and never check again). The Disposable Email Domain check flags these for free by matching known disposable domains; email verification can also return disposable at the mail-server level.

What is a role-based email address?#

An address like info@, admin@, support@ or sales@ that reaches a team inbox rather than a named person. The Role-Based Email check flags these — useful to know before a personal, name-addressed campaign, since these addresses usually aren't monitored by one individual.

Does ListPlus flag personal email addresses like Gmail?#

Yes — the Personal Email Domain check marks addresses on free consumer providers (Gmail, Yahoo, Outlook.com and similar). This is informational, not a quality problem; it just tells you the address isn't on a company domain.

Can ListPlus fix a typo in an email domain?#

Yes. The Email Domain Typo check catches common misspellings (like gmial.com instead of gmail.com) and suggests the corrected domain, which you can apply from the Analyze panel.

How do I verify whether an email is actually deliverable?#

Open the row's Record panel, or select rows and open the Enrich panel, and click Verify Email Deliverability under the Verify group. It costs 0.1 credit per email, and only when the result is valid, invalid or disposable — a catch-all, unknown or error result isn't charged.

What does a "catch-all" verification result mean?#

The domain accepts mail for any address, so the mail server can't confirm whether this specific mailbox is real. It's not an error — many legitimate companies configure mail this way — treat it as unconfirmed rather than bad.

If an email is verified, is it guaranteed not to bounce?#

No. A "valid" result means the mailbox accepted mail at the moment it was checked — it significantly lowers bounce risk but can't guarantee a future send will succeed, since mailboxes can fill up or be deleted afterward. No verification service, including this one, can promise zero bounces.

Am I charged for every email I verify?#

Only when the result is valid, invalid or disposable (0.1 credit each). Catch-all, unknown and error results aren't charged, and addresses the free checks already flagged as invalid, disposable, a typo, a role account or a test domain are marked invalid (or disposable/unknown) without spending a credit. Results are cached for 7 days, so re-checking the same address in that window doesn't cost again.