SharePoint Online: Delete a Subsite using PowerShell

Requirement: SharePoint Online PowerShell to Remove Subsite

How to Delete a Subsite in SharePoint Online?
Any user with Full Control or Manage Hierarchy permissions within a site can delete the site in SharePoint Online. To delete a subsite from SharePoint online:

• Click on Site Settings gear >> Choose "Site Settings".
• Click on "Delete this Site" link under "Site Actions" group.
  
• This leads you to the "Delete this site" page. Click on "Delete" button and confirm subsite deletion.
  
• and you'll get "Your Web site has been deleted." message in a while.

Remove SharePoint Online Subsite using Sites and Workspaces:
You can also remove a subsite in SharePoint Online using "Sites and Workspaces" link. Here is how:

1. Navigate to the parent site which contains the subsite you want to delete.
2. Click on Settings Gear >> Select Site Settings
3. On the Site Settings page, under Site Administration section, click on "Sites and Workspaces" link.
4. On the Sites and Workspaces page, click on the Delete icon next to the subsite to be deleted.
5. On the Delete This Site page, click the Delete button >> click the OK button to confirm.
   

This removes the subsite in SharePoint online. Lets see how to delete subsite in SharePoint Online using PowerShell!

Delete a subsite in SharePoint Online using PowerShell:
How to delete a subsite in SharePoint Online using PowerShell? Well, while removing subsites in SharePoint Online using web browser UI is relatively simpler, We may need PowerShell in certain cases, such as:

• When you have to delete subsites in bulk.
• If you want to delete a sub-site which has its child-subsites (You'll get this error: "There was a problem deleting Web site "/sites/Sales/apac". Sites that have subsites or certain apps can't be deleted. Please try again after deleting all subsites and removing the apps.")

Here is the PowerShell to delete a subsite in SharePoint online.

#Load SharePoint Online Assemblies
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Runtime.dll"
   
#Variables for Processing
$SiteUrl = "https://crescent.sharepoint.com/sites/Sales/apac/"
$UserName="Salaudeen@crescent.com"
$Password ="Password goes here"

try{  
    #Setup Credentials to connect
    $Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($UserName,(ConvertTo-SecureString $Password -AsPlainText -Force))

    $context = New-Object Microsoft.SharePoint.Client.ClientContext($SiteUrl)
    $context.Credentials = $credentials
    
    #get the subsite
    $web = $context.Web
    $context.Load($web)
    $context.ExecuteQuery()

    #sharepoint online powershell remove subsite
    $web.DeleteObject()
    $context.ExecuteQuery()

    Write-Host "SubSite Deleted:" $web.Title -foregroundcolor Green
}
catch{
    write-host "Error: $($_.Exception.Message)" -foregroundcolor Red
}

This PowerShell removes SharePoint Online Subsite.

How to Delete All subsites under a Site in SharePoint Online using PowerShell:
Let's wrap the above script into a reusable function to delete subsites recursively in a site collection!

#Load SharePoint Online Assemblies
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Runtime.dll"
   
#Variables for Processing
$SiteUrl = "https://portal.sharepoint.com/sites/Sales/apac/us/"
$UserName="Salaudeen@crescent.com"
$Password ="password goes here"

#Function to delete a subsite and its all child sites
Function Remove-SPOWeb() {
param(
    $WebURL = $(throw "Please Enter the Subsite URL to Remove:")
)
    try{
        #Setup Credentials to connect
        $Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($UserName,(ConvertTo-SecureString $Password -AsPlainText -Force))
  
        #Get Web information and subsites
        $Context = New-Object Microsoft.SharePoint.Client.ClientContext($webURL)
        $Context.Credentials = $credentials
        #get the subsite
        $web = $context.Web
        $context.Load($web)
        $Context.Load($web.Webs)
        $Context.executeQuery() 
 
        #Iterate through each subsite in the current web
        foreach ($Subweb in $web.Webs)
        {
            #Call the function recursively to process all subsites underneaththe current web
            Remove-SPOWeb($Subweb.url)
        }

        #sharepoint online powershell delete web
        $web.DeleteObject()
        $context.ExecuteQuery()
        Write-Host "SubSite Deleted:" $web.Title -foregroundcolor Green
        }
    catch{
        write-host "Error: $($_.Exception.Message)" -foregroundcolor Red
    }
}
 
#Call the function to remove subsite
Remove-SPOWeb -WebURL $SiteUrl

This PowerShell deletes all subsites in SharePoint Online site.

SharePoint Online PnP PowerShell to Remove Subsite 
Here is how to delete subsite using PnP PowerShell.

#Config Variables
$SiteURL = "https://crescenttech.sharepoint.com/Sales"
$SubsiteURL = "2018" # Just URL of the Subsite under parent site - NOT Relative Path

#Get Credentials to connect
$Cred = Get-Credential
 
#Connect PNP Online to Parent Web
Connect-PnPOnline -Url $SiteURL -Credentials $Cred

#sharepoint online delete subsite powershell
Remove-PnPWeb -Url $SubsiteURL -Force

The Remove-PnPWeb cmdlet permanently removes a specific subsite. However, if your subsite has any child subsites, the script will end up in error saying:
Remove-PnPWeb : There was a problem deleting Web site "/sales". Sites that have subsites or certain apps can't be deleted. Please try again after deleting all subsites and removing the apps.

How to Delete a Site with all its subsites using PnP PowerShell?

#Function to delete a subsite and its all child sites
Function Remove-PnPAllWebs([Microsoft.SharePoint.Client.Web]$Web) 
{
    #Get All Subsites of the web
    $SubWebs  = Get-PnPSubWebs -Identity $Web
    ForEach($SubWeb in $SubWebs)
    {
        #Call the function recursively to remove subsites
        Remove-PnPAllWebs($SubWeb)
    }
    #Delete the subsite
    Remove-PnPWeb -Identity $Web -Force
    Write-host -f Green "Deleted Sub-Site:"$Web.URL
}

#Config Variables
$SiteURL = "https://crescenttech.sharepoint.com/sales"

#Get Credentials to connect
$Cred = Get-Credential
 
#Connect PNP Online
Connect-PnPOnline -Url $SiteURL -Credentials $Cred

#Get the Web 
$Web = Get-PnPWeb

#sharepoint online delete subsite powershell
Remove-PnPAllWebs $Web