For as long as I can remember, cPanel has a feature called Domains (cPanel > Domains section) that allows you to create a separate file structure for additional domains:

This can be a very cost-effective way to provide hosting to more than one of your websites.

The main downside is that all domains share a common cPanel.

This means, if you're setting up hosting for someone besides yourself, you can only give them "master access" to the cPanel. As of now, cPanel doesn't allow the creation of multiple admin users.

Additionally, if you're using a content management system (CMS) such as WordPress, it's VERY important to keep everything updated such as the core files, themes, and plugins.

The NUMBER ONE reason we see accounts get compromised, is they're using an outdated piece of software which allows intruders to compromise the entire cPanel. It just takes ONE outdated plugin/theme/WordPress to create problems with all domains inside the account.

This is the main reason why I shy using this method, especially if you don't plan on logging in regularly to keep things updated.

However, if you're using this for your own use, and plan on keeping everything updated and safe, you can easily add another domain with the following steps: