Create a subsite in SharePoint Online in 2026
Microsoft recommends a flat hiearchy in SharePoint however if you need to create a subsite this can be done from the New menu in the Site Contents . If you find that Subsite isn't available on this menu it may be disabled at the tenant level. You can enable this by going to SharePoint Admin Center > Settings > Classic settings page https:// you-admin-site /_layouts/15/online/TenantSettings.aspx