# Email quality checks and verification

Source: https://listplus.ai/en/help/check-and-clean/email-quality-and-bounces
Last updated: 2026-09-25

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.

## Related topics

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.