How can I change the username of a cPanel account?
The username of a cPanel account can be changed in WHM >> Modify an Account. When changing the username of a cPanel account we recommend the new username be shorter or the same length as the original username. If the new username is longer than the old username, this may cause MySQL to truncate the cPanel account’s database names and database usernames.
More information can be found in our documentation on Modify an Account: