How ValidReach checks an address
Every check runs the same ordered pipeline and returns a status plus flags. This page explains the signals behind each status, so you can decide what to send, suppress or retry.
Signals
- Email verifier
One address at a time: format, domain and mail route, then a mailbox check where the receiving server allows it.
syntax · domain · MX · mailbox · score
- Disposable email detection
Flags temporary-inbox domains so signups and lists can keep them out of campaigns.
disposable
- Bounce email checker
Separates addresses that cannot accept mail from ones that merely look unusual, before a send.
invalid · risky
- Catch-all verifier
Recognises accept-all domains, where a mailbox check cannot confirm one address, and reports that state instead of guessing.
catchall
- Role account checker
Marks shared mailboxes such as info@ or support@, which accept mail but rarely belong to one person.
role
Pipeline order
1. Format
Is the address structurally valid?
Malformed input stops here without contacting a network.
2. Domain and MX
Does the domain exist, and does it publish a mail route?
A domain with no MX route cannot receive mail.
3. Mailbox check
Does the receiving server accept this specific address?
Where the server answers, the reply confirms or rejects the mailbox; some servers refuse or accept everything, which produces unknown or catchall.
4. Quality flags
Is the address disposable, role-based or free webmail?
Flags sit beside the deliverability result rather than replacing it.
A definitive result costs one credit. Unknown results and failed checks are refunded, so an inconclusive answer is never charged. See result fields and reason codes for the API view.
Result states
| Status | What it means | Deliverable | What to do |
|---|---|---|---|
| valid | The checks found a mailbox that accepts mail. | yes | Send. |
| invalid | Syntax, domain or the receiving server rejected the address. | no | Suppress or correct. |
| unknown | No definite answer — a timeout, a greylist or a server refusal. | not determined | Retry later; no credit is charged. |
| risky | Deliverable, but a quality signal lowers confidence. | yes | Send with care or segment separately. |
| disposable | The domain belongs to a temporary or throwaway inbox service. | yes | Block, or require a different address. |
| catchall | The domain accepts every address, so the mailbox itself is unconfirmed. | no | Treat as unconfirmed; do not count it as a clean valid. |
| role | A shared mailbox rather than a personal address. | yes | Route to a team inbox or exclude from personalised sends. |
Check a list at once with list verification or call the API. To compare a single address first, use the free verifier.