A user's username can be changed using a simple import file with three columns:
Action: Use "Edit" to tell the system that you are editing an existing user record.
User ID: Use the Echo UserID of the individual you want to edit.
Username: Use the new username.
Use the Import feature on the Users tool to update the user's username. For detailed instructions on using the user import feature, see How do I import users?
Note: For a complete guide on updating user information including account status, graduation year, email address and more, see How do I update user data?