SharePoint Site Collection Administration: Complete Guide for SharePoint Admins

Understanding SharePoint Site Collections

A site collection is the fundamental administrative unit in SharePoint Online. Every SharePoint site is part of a site collection — and understanding how site collections work is foundational to effective SharePoint administration.

In modern SharePoint Online, site collections are created automatically when you create a site. The terms "site" and "site collection" are largely interchangeable for most modern SharePoint deployments, though administrators need to understand the underlying architecture.

Site Collection Architecture

What's in a Site Collection

```

Site Collection (Top-Level Site)

├── Root Site (/)

│ ├── Document Libraries

│ ├── Lists

│ ├── Pages

│ └── Site Settings

├── Sub-sites (discouraged in modern SP)

│ └── Sub-sub-sites (strongly discouraged)

├── Site Collection Features (cross-site functionality)

├── Site Collection Administrators

├── Site Collection Content Types

├── Site Collection Recycle Bin

├── Term Store (local to site collection)

└── Storage Quota

```

Site Collection Types in SharePoint Online

| Template | Created When | Notes |

|----------|-------------|-------|

| Team Site (STS#3) | New Team site created | Group-connected or standalone |

| Communication Site (SITEPAGEPUBLISHING#0) | New Communication site | Broadcast-focused |

| Hub Site | Admin promotes a site | Organizes other sites |

| Root Site Collection | Tenant creation | contoso.sharepoint.com |

| OneDrive Personal | User activated | personal/username |

| Search Center | Admin provisioned | Legacy — use modern search |

| Redirect Site | URL redirect | Preserves old URLs after migration |

Site Collection Administration in SharePoint Admin Center

Accessing Admin Center

SharePoint Admin Center: admin.microsoft.com → SharePoint Admin Center (or directly at contoso-admin.sharepoint.com)

Active Sites view shows all site collections with:

• URL, site name, template
• Storage used / allocated
• Last activity date
• Primary admin
• Hub association
• External sharing setting

Site Collection Creation

```powershell

# Create new Team site (non-group)

Connect-SPOService -Url "https://contoso-admin.sharepoint.com"

New-SPOSite `

-Url "https://contoso.sharepoint.com/sites/finance-reporting" `

-Owner "[email protected]" `

-StorageQuota 5120 ` # 5GB in MB

-Title "Finance - Reporting" `

-Template "STS#3" `

-TimeZoneId 10 # Eastern Time

```

```powershell

# Create Communication Site

New-SPOSite `

-Url "https://contoso.sharepoint.com/sites/corporate-comms" `

-Owner "[email protected]" `

-StorageQuota 10240 `

-Title "Corporate Communications" `

-Template "SITEPAGEPUBLISHING#0"

```

```powershell

# Create via PnP (more options)

Connect-PnPOnline -Url "https://contoso-admin.sharepoint.com" -Interactive

New-PnPSite -Type TeamSiteWithoutMicrosoft365Group `

-Title "Finance - Annual Reports" `

-Url "https://contoso.sharepoint.com/sites/finance-annual-reports" `

-Owner "[email protected]" `

-Lcid 1033 `

-TimeZone 10

```

Storage Quota Management

Understanding Storage

SharePoint Online storage pool:

• 1TB per tenant + 10GB per licensed user automatically allocated
• Example: 1,000 licensed users = 1TB + 10TB = 11TB total pool
• All site collections share this pool unless per-site quotas are set

```powershell

# Check total tenant storage

$tenantInfo = Get-SPOTenant

Write-Output "Storage allocated: $($tenantInfo.StorageQuota) MB"

Write-Output "Storage used: $($tenantInfo.StorageQuotaAllocated) MB"

# Check all sites by storage

Get-SPOSite -Limit All | Select-Object Url, StorageUsageCurrent, StorageQuota |

Sort-Object StorageUsageCurrent -Descending |

Select-Object -First 20

# Set quota for specific site (prevent one site consuming all storage)

Set-SPOSite -Identity "https://contoso.sharepoint.com/sites/large-archive" `

-StorageQuota 51200 ` # 50GB

-StorageQuotaWarningLevel 45000 # Warn at 45GB

```

Storage Optimization

Sites accumulate storage from:

• Document versions (every save creates a new version)
• Recycle bin (93-day retention)
• Temporary files and test content

```powershell

# Find libraries with excessive version history consuming storage

Connect-PnPOnline -Url "https://contoso.sharepoint.com/sites/finance-reporting" -Interactive

$lists = Get-PnPList | Where-Object { $_.BaseTemplate -eq 101 } # Document libraries only

foreach ($list in $lists) {

$items = Get-PnPListItem -List $list -Fields "ID", "File_x0020_Size"

Write-Output "Library: $($list.Title) — Items: $($items.Count)"

}

# Clear recycle bin to reclaim storage

Clear-PnPRecycleBinItem -All -Force

```

Site Collection Administrators

Site Collection Administrators have full control over the entire site collection — including content others have restricted access to. Manage carefully.

```powershell

# Get all site collection admins across the tenant

$sites = Get-SPOSite -Limit All

foreach ($site in $sites) {

$admins = Get-SPOUser -Site $site.Url | Where-Object { $_.IsSiteAdmin -eq $true }

foreach ($admin in $admins) {

Write-Output "$($site.Url) — Admin: $($admin.LoginName)"

}

}

# Add site collection admin

Set-SPOUser -Site "https://contoso.sharepoint.com/sites/finance-reporting" `

-LoginName "[email protected]" `

-IsSiteCollectionAdmin $true

# Remove site collection admin

Set-SPOUser -Site "https://contoso.sharepoint.com/sites/finance-reporting" `

-LoginName "[email protected]" `

-IsSiteCollectionAdmin $false

```

Best Practice: Site Collection Admin Governance

• Maximum 2-3 site collection admins per site (primary owner + IT backup)
• Quarterly audit: Review all site collection admins across tenant
• Remove former employees immediately (automate via HR system trigger)
• Document all admin assignments in a SharePoint governance register

Site Features and Feature Management

SharePoint features activate/deactivate specific functionality at the site or site collection level.

```powershell

# List activated features on a site

Connect-PnPOnline -Url "https://contoso.sharepoint.com/sites/finance-reporting" -Interactive

Get-PnPFeature -Scope Web | Select-Object DisplayName, Id, Scope

# Activate a feature

Enable-PnPFeature -Identity "87294c72-f260-42f3-a41b-981a2ffce37a" ` # Publishing Infrastructure

-Scope Web

# Deactivate a feature

Disable-PnPFeature -Identity "87294c72-f260-42f3-a41b-981a2ffce37a" -Scope Web

```

Common Features to Know

| Feature | GUID | Purpose |

|---------|------|---------|

| SharePoint Server Publishing | 87294c72-f260-42f3-a41b-981a2ffce37a | Publishing workflows, page layouts |

| Metadata Navigation | 7201d6a4-a5d3-49a1-8c19-19c4bac6e668 | Library metadata filters |

| Content Organizer | 7ad5272a-2694-4349-953e-ea5ef290e97c | Automated document routing |

| Document Sets | 3bae86a2-776d-499d-9db8-fa4cdc7884f8 | Document set content type |

| In-Place Records | da2e115b-07e4-49d9-bb2c-35e93bb9fca9 | Declare records in-place |

Hub Site Administration

Hub sites are site collections promoted to hub status. They organize associated sites and share navigation and search.

```powershell

# Register a site as a hub site

Connect-SPOService -Url "https://contoso-admin.sharepoint.com"

Register-SPOHubSite `

-Site "https://contoso.sharepoint.com/sites/corporate-hub" `

-Principals @("[email protected]")

# Associate a site with the hub

Add-SPOHubSiteAssociation `

-Site "https://contoso.sharepoint.com/sites/hr-policies" `

-HubSite "https://contoso.sharepoint.com/sites/corporate-hub"

# Set hub site logo and theme

Set-SPOHubSite "https://contoso.sharepoint.com/sites/corporate-hub" `

-LogoUrl "/sites/corporate-hub/SiteAssets/hub-logo.png" `

-Title "Corporate Hub"

# List all hub sites

Get-SPOHubSite | Select-Object Title, SiteUrl, SiteId

```

Site Collection Lock States

SharePoint sites can be locked to prevent access or writing:

```powershell

# Lock states: Unlock, NoAccess, ReadOnly, NoAddAndDeleteFiles

# Set site to read-only (good for archiving active sites before deletion)

Set-SPOSite -Identity "https://contoso.sharepoint.com/sites/old-project" `

-LockState ReadOnly

# Unlock a site

Set-SPOSite -Identity "https://contoso.sharepoint.com/sites/restored-site" `

-LockState Unlock

# Block all access (while investigating security incident)

Set-SPOSite -Identity "https://contoso.sharepoint.com/sites/compromised-site" `

-LockState NoAccess

```

Recycle Bin Management

SharePoint has a two-stage recycle bin:

• First-stage: User's site recycle bin (93 days)
• Second-stage: Site collection recycle bin (admins only, additional time)

```powershell

# Get all items in first-stage recycle bin

Connect-PnPOnline -Url "https://contoso.sharepoint.com/sites/finance-reporting" -Interactive

$recycleBin = Get-PnPRecycleBinItem -FirstStage

Write-Output "Items in first-stage recycle bin: $($recycleBin.Count)"

$totalSize = ($recycleBin | Measure-Object -Property Size -Sum).Sum / 1MB

Write-Output "Total size: $([Math]::Round($totalSize, 2)) MB"

# Restore specific item

Restore-PnPRecycleBinItem -Identity $recycleBin[0].Id

# Clear second-stage recycle bin (permanent deletion)

Get-PnPRecycleBinItem -SecondStage | Clear-PnPRecycleBinItem -Force

```

External Sharing Control

```powershell

# Set external sharing at site level (overrides tenant policy for more restrictive)

Set-SPOSite `

-Identity "https://contoso.sharepoint.com/sites/client-portal" `

-SharingCapability ExternalUserSharingOnly ` # Guest accounts only

-SharingAllowedDomainList "client1.com client2.com" `

-SharingDomainRestrictionMode AllowList `

-ExternalUserExpirationInDays 365

# Disable external sharing for sensitive site

Set-SPOSite `

-Identity "https://contoso.sharepoint.com/sites/finance-audit" `

-SharingCapability Disabled

```

Health Monitoring and Reporting

```powershell

# Get sites with no activity in 90 days (stale sites)

$allSites = Get-SPOSite -Limit All

$staleSites = $allSites | Where-Object {

$_.LastContentModifiedDate -lt (Get-Date).AddDays(-90) -and

$_.Template -notlike "*REDIRECT*" -and

$_.Template -notlike "*MY*" # Exclude OneDrive

}

Write-Output "Stale sites (90+ days): $($staleSites.Count)"

$staleSites | Select-Object Url, LastContentModifiedDate, StorageUsageCurrent |

Export-Csv "C:ReportsStaleSites.csv" -NoTypeInformation

# Sites approaching storage quota

$nearQuota = $allSites | Where-Object {

$_.StorageQuota -gt 0 -and

($_.StorageUsageCurrent / $_.StorageQuota) -gt 0.8

}

Write-Output "Sites at 80%+ storage quota: $($nearQuota.Count)"

```

Bulk Operations

```powershell

# Apply same settings to all sites in a hub

$hubAssociatedSites = Get-SPOSite -Limit All |

Where-Object HubSiteId -eq "hub-site-id-here"

foreach ($site in $hubAssociatedSites) {

# Apply theme

Connect-PnPOnline -Url $site.Url -Interactive

Set-PnPWebTheme -Theme "Contoso Brand Theme"

# Set external sharing off

Set-SPOSite -Identity $site.Url -SharingCapability Disabled

Write-Output "Updated: $($site.Url)"

}

```

SharePoint Admin Center vs. PowerShell

| Task | Admin Center | PowerShell |

|------|-------------|-----------|

| Create one site | ✅ Easier | ✅ Also works |

| Create 50 sites | ❌ Manual | ✅ Scripted |

| Audit all site admins | ❌ Not available | ✅ Available |

| Apply theme to all sites | ❌ Manual per site | ✅ Scripted |

| Generate storage report | Partial | ✅ Full detail |

| Manage lock states | ✅ Available | ✅ Also works |

| Feature activation | Per site only | ✅ Bulk scripted |

For any operation affecting more than 5 sites, use PowerShell.

Conclusion

Effective SharePoint site collection administration requires both understanding of the architecture and proficiency with PowerShell. The SharePoint Admin Center handles day-to-day tasks, but bulk operations, reporting, governance enforcement, and automation require the PnP PowerShell module and SPO PowerShell.

EPC Group provides SharePoint administration services ranging from day-to-day support contracts to governance program design and PowerShell automation. Contact us to discuss your administration needs.