There are 3 tiers for the website builder plans: Starter, Professional, and E-commerce.
The Starter Plan is included with all our Basic Hosting and Starter Hosting packages.
The Professional Site Builder is available on our Unlimited Hosting XR, Unlimited Hosting, Unlimited Windows, Unlimited SSD, Ultra Hosting and Ultra Windows plans.
The Ecommerce Site Builder is included with the Business Enterprise, Business Premium and Business Standard plans.
You can take a look at the full list of included site builder features here.