Email verification

Easily verify your email lists

For your larger email lists, you will want to visit the My lists section where you will be able to upload and verify CSV or TXT files. If you are a MailerLite user, you will also be able to utilize our integration to verify your existing MailerLite groups. 

Uploading your email list

  • 1

    Click on My lists (top menu)

  • 2

    Click on Verify new list button

  • 3

    Click the Select button for My Computer

  • 4

    Search and select the file to upload and verify → CSV and TXT files only

Note: MailerCheck will only accept CSV and TXT files. Excel files are not supported and will need to be converted to CSV.

During the upload process, MailerCheck will compare the number of emails in the uploaded list with the number of credits available within the account. To verify the list, the number of credits in the account must be equal to or greater than the number of emails in the list. 

If the account has enough credits

  • 5

    Click on the Verify list button to begin verifying your list


If the account does not have enough credits

  • 5

    Click on the purchase more credits link to purchase more credits. After you’ve purchased the necessary credits, come back to My lists to verify your uploaded list.


Verification results

Verifying your emails is just the first part of cleaning your email list. The real value comes when you understand how your emails are categorized and then you adjust your email lists according to our recommendations.

  • 1

    Click on My lists (top menu)

  • 2

    Click on View details for one of the lists previously uploaded


The circle chart visualizes the types of email statuses found in your list during the verification process. The number in the center is the number of emails that were verified on your list.

The right side of the page displays individual statuses, along with the number of emails within a given status.  

The download button will download a CSV file for a specific status, or you can download all results.

Note: Unknown statuses will not be charged. We only charge credits for emails we can verify.



Email is safe to send.


Recipient's mail server will accept emails to this address, but we cannot guarantee this email address belongs to a person.


We are unable to determine if the email is valid or not valid. Use caution when sending.

Mailbox full

Recipient’s inbox is full and may not be able to receive new emails. Use caution when sending.

Mailbox not found

Recipient’s inbox does not exist. Do not send.

Syntax error

Email is not valid. Do not send to.


Email address has a typo. Correct email address and retest.


These email addresses should be removed from your lists. These are temporary email addresses people use to avoid getting spam in their inbox.