Mailing lists are a good way to send a message or series of messages to many people at once. For example, many companies use mailing lists to email newsletters, promotional offers, or information about product updates to subscribers.

There are two primary methods for adding subscribers to a mailing list. If there are only a few emails to add to the mailing list, domain administrators or list moderators can manually add individual subscribers. If there are a large number of emails to add to a mailing list, they can upload a .csv (Comma Separated Values) file that lists all of the subscriber emails.

NOTE: At a bare minimum, the .csv file must contain a column named "EmailAddress". Any additional columns in the .csv file will be added to the Subscriber Fields for the corresponding subscriber/email address. 

For more information on adding subscribers individually to a mailing list, refer to the KB article Add Subscribers to Mailing Lists.

Follow these steps to add multiple subscribers to a mailing list at once:
  1. Log in as the domain administrator.
  2. Click the Domain Settings icon.
  3. When the Domain Settings load, click Mailing Lists in the navigation pane. A list of available mailing lists will load in the content pane.
  4. Click on the desired mailing list.
  5. When the list's Options open, click on the Subscribers tab. A list of current subscribers to this mailing list will load in the content pane, if there are any.
  6. Click on the Actions (...) button. 
  7. From the dropdown menu, select Import CSV File
  8. Click Upload in the content pane toolbar.
  9. The Upload Subscribers modal opens. Click in the upload box and then select a .csv file to upload and click Save. (Alternatively, you can drag a .CSV file into the upload box.)
  10. Depending on the file size, it may take a few moments to upload.
  11. Once finished, your new subscribers will be displayed.