There is Remove the Domain function of cPanel that allows removing a domain from your account.
Go to cPanel
Click on Domains icon in Domains section:
From the list choose the domain you want to delete:
Click on the Remove Domain button and confirm that you want to remove the domain from your cPanel account:
Before deleting a domain read the information below:
- It is impossible to remove the main domain.
- We recommend doing a full backup of your hosting account before you delete a domain.
- The root domain folder which includes the website content will still be able in the account after the domain name has been removed.
- When you remove a domain with email accounts, those email accounts will not appear in the Email Accounts menu. Though, the mail folders for the email accounts continue to exist on the server. If you add the domain again, the email accounts will reappear in the Email Accounts menu.