please read Update below.
Microsoft recommends a “flat structure”, i.e. no subsites. Instead of subsite you should have a separate site collection, and if you need a hierarchy and navigation – use Hub sites. Somebody from Microsoft even said “Site is a new Folder”. And it makes sense. So, in Office 365 SharePoint admins usually “disable” Sub Sites creation at tenant level.
It’s done like this. You just remove ‘Let users create sites from the SharePoint start page and OneDrive’:
But sometimes you still need subsites for a reson. Did you know that you still can create subsite if “creation is disabled” at tenant level? Let me explain how it is done.
If subsites creation is allowed, you can see it like this:
How SPO admins disable subsites creation in SharePoint CA:
As you see, Subsites are not really disabled, but only the button to create subsites is hidden: “This controls whether the Subsite command appears on the New menu on the Site contents page”. Prove:
As a result, users are not creating Subsites as they are not seeing “Create Subsite” option in SharePoint Online.
But actually there are at least 3 ways to create a SubSite.
- Switch to Classic Mode (Create a SubSite in Classic mode) then switch back to modern experience
- Create a Subsite from “Site Settings” -> “Sites and Workspaces” page
- use PowerShell
Option 1. Create a SubSite in Classic mode.
Step 1: Select “Site Contents” page
Step 2: Click “Return to classic SharePoint”
Step 3: Create SubSite
Option 2. Create a SubSite from “Sites and Workspaces” page
Step 1: Go to “Site Settings”
Step 2: Select “Sites and Workspaces” page (site/_layouts/15/mngsubwebs.aspx)
Step 3: Create a SubSite
Option 3: use PowerShell PnP
Step 1: Install PowerShell PnP module
Step 2: Connect to your site
Step 3: create a SubSite
# working in PowerShell 5 (PowerShell for Windows) Install-Module SharePointPnPPowerShellOnline Connect-PnPOnline -Url <your site Url> -UseWebLogin New-PnPWeb -Url "<new Web Url>" -Title "MySubSite" -Template "STS#3" # working in PowerShell 7 Install-Module PnP.PowerShell $siteUrl = "https://yourTenant.sharepoint.com/sites/YourSite" $webUrl = "subsite01" $webTitle = "Sub-Site 01" Connect-PnPOnline -Url $siteUrl -UseWebLogin New-PnPWeb -Url $webUrl -Title $webTitle -Template "STS#3"
Microsoft is going to implement a real “disable subsites” feature.
Have a look:
SharePoint updates to options for disabling subsite creation.
MC276029 · Published Aug 6, 2021
This new update … prevents users from being able to create subsites using alternate paths when the subsite setting is disabled.
When this will happen: … will begin rolling this out in late September and expect to complete rollout mid-October.
… when disabling subsite creation, not only will the subsite option be hidden from the command bar including classic but also users will not be able to create new subsites directly through an URL or API.
The option: Hide the Subsite command has been renamed to Disable subsite creation for all sites and will also hide the subsite creation command (including classic) and disable users from being able to create new subsites through a URL or API.
The option: Show the Subsite command only for classic sites, has been renamed to Enable subsite creation for classic sites only.
The option: Show the Subsite command for all sites, has been renamed to Enable subsite creation for all sites.
Note: Instead of using subsites, we recommend that you use hub sites. SharePoint hub sites allow you to group similar topics and content together using modern architecture design.
What actually happens after this update
Yes, buttons were renamed – e.g. “Disable subsite creation for all sites”
You can still go to the “Site Settings > Sites and Workspaces”, but when you try to create a new subsite – you get error message
“Sorry, something went wrong. New subsites are not available for your organization. Create a new site instead.”