Cleaning a list with email verification
Learn when to verify a list in Sendora, how to interpret valid, invalid, catch-all, disposable, or unknown results, and which addresses to keep.
A list can contain mistyped, deleted, temporary, or inactive addresses. Verifying it before a campaign helps identify these risks, reduce bounces, and protect your sender reputation.
Verification does not replace consent or responsible collection. A technically valid address does not mean its owner wants to receive your emails.
When should you verify a list?
Verification is especially useful:
- after importing a CSV or Excel file;
- before the first send to an old or unused list;
- when your bounce rate begins to rise;
- after collection involving substantial manual entry;
- before an important campaign when the previous check is old.
You do not need to repeat the check before every campaign. In Sendora, contacts verified during the last 30 days are normally excluded from a new charge unless you deliberately choose to verify them again.
Verify a complete list or selected contacts
On the Lists page, use the verification action for the relevant list to check every address that needs it. Sendora displays the contact count, your balance, and the credits that will remain after the operation.
You can also select individual contacts on the Contacts page. This is useful for testing a new import, checking a priority segment, or completing part of a list when your credit balance is lower than its total size.
How credits work
- each checked address uses one credit;
- credits are purchased separately from the subscription;
- they remain available until used;
- if your balance is insufficient, verify the contacts covered by it or purchase a pack.
Understand each result
A status appears next to every processed contact. These are the usual recommended decisions.
Valid
The address exists and can receive email. Keep it when the contact has agreed or can otherwise legitimately receive your message.
Invalid
The address does not exist, is inactive, or cannot receive the message. Sendora automatically excludes it from campaigns to prevent a permanent bounce.
Catch-all
The domain accepts messages without confirming the exact mailbox. The result is uncertain. Keep it only when its source is reliable and the contact matters, then watch for bounces.
Disposable
This is a temporary address designed to disappear. Sendora automatically excludes it from campaigns.
Unknown
The server did not allow the address to be confirmed. Treat it as neither valid nor invalid. Retry later or keep it only when its source and value are clear.
Error
A technical issue prevented verification. Wait and retry the check. Do not exclude the contact based on this result alone.
Sendora automatically excludes invalid and disposable addresses from campaigns. Catch-all and unknown contacts are not excluded automatically, so decide based on their source, age, and commercial relevance.
What happens during verification?
Sendora submits the address to the specialist service MillionVerifier for the technical check and displays the result inside your account. This disclosure provides transparency, but you do not need a MillionVerifier account or need to leave Sendora.
The check examines factors such as syntax, domain, and the receiving server's declared ability to accept a message. It does not send a campaign to the contact and cannot guarantee placement in the primary inbox. Content, domain authentication, and sender reputation still matter.
Prepare the final list
- keep valid addresses collected legitimately;
- let Sendora automatically exclude invalid and disposable addresses;
- isolate catch-all and unknown results if you want to test them separately;
- always exclude unsubscribed contacts, even when their address is valid;
- after sending, review bounces and clean the list again when needed.
Verification improves list quality, but the strongest protection is clear, recent collection based on a real relationship with recipients.
After sending, use Understanding your email campaign statistics to monitor bounces and other quality signals.