Are hubs the new SharePoint site collection?

I deliver presentations on SharePoint hubs frequently, and one of the questions I get asked in every session is:

Are hubs the new SharePoint site collections?

This question comes from SharePoint administrators, end-users, and site owners alike. Many of us have been working for more than a decade to build hierarchies of SharePoint sites. In the SharePoint 2007 and SharePoint 2010 days, we prided ourselves in building and effectively managing deep webs of sites to combat the urban sprawl of site collections.

Now the SharePoint world is flat and we build each of our modern SharePoint sites in their own site collections. This affords a multitude of benefits, including: configuring site collection settings to meet our site’s exact needs, keeping our site URLs short, and avoiding the constant struggle to migrate sites from one site collection to another based on organizational changes. But we still need to figure out how to connect our flat SharePoint sites together in a meaningful way. This is where SharePoint hubs come in.

Hubs provide a familial, logical tie between SharePoint sites. With hubs, you can unify SharePoint site branding, provide a common navigation experience, and roll up news and events in a centralized display. Hubs enhance content discovery by tying sites together for easy browsing. Hubs are also flexible and support your organization as it evolves. Simply assign your site to a new hub and your site’s branding is automatically updated.

But we still have a challenge. We need our end-users and SharePoint site owners to understand 2 key things:

Site collections no longer contain hierarchies of sites; they’re now “flat” and contain only one site.
SharePoint hubs are not a new type of site collection. Site collections were physical constructs that created hierarchical site structures (aka parent and child sites). Hubs provide a logical tie between SharePoint sites, but this logical tie has nothing to do with physical storage. Each flat site associated with a hub exists in its own independent site collection.

Episode 32 of the Microsoft 365 Voice dives deeper into this topic. We explore the definition of classic and modern SharePoint sites, share tips on how you can start transitioning your classic sites, and explain why hubs are not site collections. We hope you enjoy this episode!