Yes, you can change your cPanel account username. This feature is not found in your cPanel because cPanel accounts are tied to the username, your home directory, configurations, email, etc.

To request a cPanel account username change:
1. Go to the Hosting List menu in the bar on the left. Click Manage next to the subscription:

2. On the next page, chose the Change cPanel username in the Account Actions drop-down menu:

3. Enter the new cPanel username and agree to the disclaimer:

Allow the system to validate your request (this can take between 2-3 minutes). You will receive a message regarding the successful cPanel username change as well as a confirmation email to the email address associated with your Namecheap account.

Note: it is not possible to change the cPanel username for a suspended hosting package.

We should also warn you about possible issues which may occur after such a change:.

-If you have a website which is using a database, the site's MySQL configuration should be changed to the new account username accordingly.It is usually done by editing the configuration file.
-The new cPanel username should be the same length or shorter in order to prevent MySQL from truncating the account's database names and database usernames.