Storage Management at Scale

1. Why Storage Matters

SharePoint Online storage is a finite resource that directly impacts your Microsoft 365 costs and your users' productivity. Every Microsoft 365 tenant receives a base allocation of SharePoint storage, plus additional storage per licensed user. When your tenant approaches or exceeds its storage quota, users may be unable to upload files, sync may fail, and critical business workflows can be disrupted.

For organisations managing multiple tenants, storage management becomes even more complex. Each tenant has its own quota and usage patterns, and storage consumption tends to grow steadily over time as users create and share more content. Without proactive monitoring, it is common for tenants to approach their storage limits unexpectedly, leading to urgent and expensive remediation efforts.

SPScan monitors storage usage across all of your connected tenants, giving you visibility into how storage is being consumed at the tenant, site, and library level. By tracking storage trends over time and alerting you when thresholds are approached, SPScan helps you prevent capacity issues before they impact your users or require purchasing additional storage from Microsoft.

2. Storage Scanning

During each scan, SPScan queries the Microsoft Graph API to collect storage usage data for every site in your tenant. This includes the total storage used by each site, the storage quota assigned to the site (if individual site quotas are configured), and the number of files and their sizes. The data is stored historically so you can track changes over time.

The storage overview page for each tenant shows a breakdown of storage by site, sorted by usage. This makes it immediately obvious which sites are consuming the most storage and where remediation efforts will have the greatest impact. You can also see the overall tenant storage usage as a percentage of the allocated quota, giving you a clear picture of how much headroom you have.

SPScan also tracks storage growth rates, which is critical for capacity planning. If a site's storage is growing by 500 MB per month, you can project when it will hit its quota and plan accordingly. This forward-looking analysis is far more valuable than simply monitoring current usage, because it gives you time to take action before problems occur.

3. Version Bloat

One of the most common causes of excessive storage consumption in SharePoint is version bloat. SharePoint's versioning feature keeps a copy of a file every time it is modified, which is valuable for document recovery and audit trails. However, the default version limit is often set to 500 versions, and frequently edited files can accumulate hundreds of versions that consume significant storage.

Consider a 10 MB PowerPoint file that is edited daily. With 500 version history entries, that single file could consume up to 5 GB of storage. Multiply this across hundreds of frequently edited files and you can see how version bloat quickly becomes the largest consumer of SharePoint storage. The problem is that most administrators are unaware of the scale of version bloat because it is hidden behind the file's primary size in most SharePoint views.

SPScan helps you identify sites and libraries where version bloat is most severe by comparing actual storage consumption against file counts and sizes. When the storage used by a library significantly exceeds the total size of its current files, version history is likely the cause. Armed with this information, you can adjust version limits, run version cleanup scripts, or implement version retention policies to reclaim storage.

4. Threshold Alerts

SPScan can alert you when storage usage exceeds configurable thresholds. The most common threshold is a percentage of the tenant's total storage quota, such as 80% or 90%. When the threshold is crossed, SPScan sends a notification through your configured alert channels so you can take action before the tenant runs out of space.

You can also set up alerts for individual site storage thresholds if you have assigned site-level quotas. This is useful for organisations that allocate specific storage budgets to departments or projects. If a site exceeds its allocated quota, the responsible team can be notified directly without involving the central IT team.

We recommend setting up at least two storage threshold alerts: a warning at 80% of the tenant quota and a critical alert at 90%. The warning gives you time to plan and implement remediation, while the critical alert signals that immediate action is needed. For MSPs, these alerts prevent the uncomfortable situation of a client discovering they are out of storage before you do.

5. Storage Reports

SPScan provides CSV storage reports that give you detailed data for analysis and planning. The storage report includes every site in the tenant with its current storage usage, quota, file count, and last modified date. You can import this CSV into a spreadsheet application to sort, filter, and create charts that help you understand storage consumption patterns.

The storage PDF report provides a formatted summary suitable for sharing with stakeholders. It includes the top sites by storage consumption, overall tenant usage, and trend data showing how storage usage has changed over recent scan periods. This report is useful for client review meetings, budget planning discussions, and capacity management reviews.

For MSPs managing many tenants, the file-level CSV export is particularly valuable. It lists individual files sorted by size, making it easy to identify the largest files consuming storage across a tenant. Combined with version bloat analysis, this data gives you a clear remediation roadmap: address the largest files and the most version-heavy libraries first for maximum storage reclamation with minimum effort.