Change default root Communication site to Classic site in SharePoint Online

Question

I have a brand new tenancy and the Communication site is the default root site. Can I change the default site to a classic site for example?

Thanks in Advance.

Answer 1

Could you tell me whether you want to replace the root site with other classic site or change the root site from modern experience to classic?

1.Replace the root site with other classic site：

Quote from Microsoft article, "The site you select as the new root site must be a communication site (SITEPAGEPUBLISHING#0) or a modern team site that isn't connected to a Microsoft 365 group (STS#3) and where the publishing feature has never been activated."

Therefore, classic site couldn't be root site.

More information about replacing root site, please refer to the following article:

https://docs.microsoft.com/en-us/sharepoint/modern-root-site#replace-your-root-site

2.Change the root site from modern experience to classic:

Communication site is a modern site, we couldn’t change the whole communication site from modern to classic site directly.

Modern experience is designed to be compelling, flexible, and more performant. It is the current trend of SharePoint Online, we suggest you use modern site.

More information about modern and classic experience, please refer to the following article:

https://support.microsoft.com/en-us/office/sharepoint-classic-and-modern-experiences-5725c103-505d-4a6e-9350-300d3ec7d73f