When EmailKit verifies an email address, it returns a detailed result explaining the deliverability of that address. This guide explains what each result means and how to act on it.
Every verified email receives one of four statuses:
The email address is valid, the mailbox exists, and it can receive emails. It is safe to send to this address.
Common sub-reasons:
Valid mailbox — The mail server confirmed the mailbox exists and is accepting mail
The email address is invalid or cannot receive emails. Do not send to this address.
Common sub-reasons:
Mailbox not found — The email address doesn't exist on the mail server
Domain not found — The domain doesn't exist or has no DNS records
No MX records — The domain exists but isn't configured to receive email
Invalid syntax — The email format is invalid (e.g., missing @, invalid characters)
Mailbox full — The recipient's mailbox is full and cannot accept new messages
Mailbox disabled — The account has been deactivated or suspended
The email might be deliverable but could cause problems. Use caution when sending to these addresses.
Common sub-reasons:
Catch-all domain — The server accepts mail for any address at that domain, so we can't confirm the specific mailbox exists
Disposable email — The email uses a temporary/throwaway service (e.g., Guerrilla Mail, Mailinator)
Role-based address — Generic addresses like info@, admin@, sales@, support@ — these often have multiple recipients or automated handling
Low quality — The address shows signs of being low-quality or inactive
We couldn't determine the deliverability of this email. Retry later or verify manually.
Common sub-reasons:
Timeout — The mail server didn't respond in time
Connection error — Couldn't connect to the mail server
Rate limited — The mail server is temporarily blocking verification attempts
Server error — An unexpected error occurred during verification
Send to: Deliverable addresses only
Consider removing: Risky addresses (especially disposable and role-based)
Never send to: Undeliverable addresses
Retry later: Unknown addresses
Send to: Deliverable and some Risky addresses (catch-all and role-based are usually fine for transactional email)
Never send to: Undeliverable addresses
Remove all Undeliverable addresses
Flag Risky addresses for review
Re-verify Unknown addresses in a few hours
Status | Charged? |
|---|---|
Deliverable | Yes (1 credit) |
Undeliverable | Yes (1 credit) |
Risky | Yes (1 credit) |
Unknown | Depends on sub-reason |
System errors (our infrastructure issues) are not charged. Timeouts and mail server issues are charged because we still performed the verification work.
