Knowledge base

Email verification

All MailerSend Premium plan accounts include a number of credits for email verification. If you have sufficient credit, you can verify a list of email addresses by clicking on Email verification in the left-hand menu.

To verify a new list, click the Verify new list button and upload a CSV file. Excel files are not supported and will need to be converted to CSV. If the file has more than one column, you’ll be asked to choose which column of emails you want to verify. 

Once the file is imported, you’ll be shown the number of credits the list verification will require. If you have sufficient credits, you can click on Verify list. If not, you can purchase additional credits on the Plan & Billing page.

Note: One email is one verification credit.

After selecting Verify list, the verification will happen in the background, so you’re free to navigate to other pages or grab a coffee.

Reviewing the email 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 adjust your email lists according to our recommendations.

To see the details of your verified list, click on Manage next to the relevant list on the Email verification page.

In the email list verification results, you can see all verified emails and their statuses according to our extensive series of checks. 

The pie chart visualizes the 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 that each status has been assigned to.  

To download a CSV file detailing the results for a specific status or to download all results, simply select the attributes you want to include, or click Select all, and click the Download Selected button.

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

What do the statuses mean?

Send to

Valid

Email is safe to send.


Risky

Catch-all

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

Mailbox full

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

Role-based

Email is role-based and may not be associated with a single, specific person but a group of people.

Past delivery issues

We have detected past delivery issues while sending to this email address. 

Unknown

We are unable to determine if the email is valid.

Do not send to

Syntax error

The email address is not valid.

Typo

The email address has a typo. Correct the email address and retest.

Mailbox not found

Recipient’s inbox does not exist.

Disposable

The email address leads to a temporary inbox and should be removed from your lists.

Mailbox blocked

The email address’ mailbox is blocked by its service provider due to poor sending practices.

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