SharePoint: The Ever-Growing Storage Challenge

Why SharePoint grows out of control

The uncontrolled growth of SharePoint rarely stems from a single cause. It is the combination of multiple factors, many of them enabled by default, that creates the perfect storm of overflowing storage.

• history Automatic versioning: SharePoint retains up to 500 versions of every file by default. A 10 MB document that is frequently edited can consume 5 GB in old versions alone. Most organisations never reduce this limit because they are unaware of its impact on storage.
• attach_file Attachments and duplicate files: when users share files via Teams, Outlook or OneDrive, copies are generated in multiple locations. A single 50 MB PDF can exist in the Teams channel, in the sender's OneDrive and in the project site library, tripling the space consumed.
• sync OneDrive synchronisation: the OneDrive sync client automatically copies SharePoint folders to the user's desktop. When users drag personal files into synced folders, these end up in SharePoint without the site owner's knowledge.
• delete_forever Lack of retention policy: without explicit policies, data is never deleted. Completed projects from years ago, obsolete drafts and Teams meeting recordings accumulate indefinitely. The second-stage recycle bin also retains deleted items for an additional 93 days.

SharePoint limits you need to know

Microsoft defines strict limits for SharePoint Online that, once reached, degrade performance or block operations. Understanding them is essential for planning governance. The most relevant ones, according to the official Microsoft documentation, are:

• database 25 TB per site collection: this is the maximum storage limit per site collection. Once reached, no new files can be uploaded until space is freed or an increase is requested from Microsoft.
• list 30 million items per library or list: although the theoretical limit is high, performance starts to degrade significantly beyond 300,000 items if indexed and filtered views are not used correctly.
• upload_file 250 GB per individual file: the maximum size for a single file is 250 GB, but uploading files larger than 10-15 GB already presents timeout and performance issues in practice.
• speed Throttling and rate limiting: SharePoint Online applies throttling when it detects excessive API usage. Automated migration or mass cleanup operations can be slowed down, affecting backup and governance tools.

Beyond hard limits, there is a less visible effect: progressive performance degradation. When a library exceeds 100,000 items or a site accumulates several terabytes, searches slow down, OneDrive synchronisation fails more frequently and content indexing operations take hours to complete.

Hidden costs of SharePoint storage

The most obvious cost is additional storage licensing. Microsoft 365 allocates a 1 TB base per organisation plus 10 GB per purchased licence. When that runs out, additional storage must be purchased at a cost that, depending on the Enterprise agreement, can be around EUR 0.20/GB/month. For an organisation with 10 TB of extra storage, that amounts to EUR 2,000/month or EUR 24,000/year in additional space alone.

But there are less visible costs that can far exceed the licensing expense:

• trending_down Degraded performance: user productivity decreases when searches are slow, synchronisation fails and navigating libraries with thousands of documents becomes tedious. This cost is difficult to quantify but very real.
• gavel Compliance risk: without retention policies, the organisation stores data that should have been deleted. Under the GDPR, retaining personal data beyond the necessary period is an infringement that can result in significant penalties.
• support_agent Operational burden on IT: managing space requests, investigating sync errors, resolving file conflicts and responding to data audits consumes hours of work from the support and administration team.

Governance strategies to control growth

Storage governance in SharePoint is not a one-off project: it is an ongoing process that combines policies, automation and user awareness. The most effective strategies are:

• policy Retention policies: define retention periods by content type using Microsoft Purview. For example: active project documents with no limit, completed project documents 2 years, meeting recordings 90 days, drafts 30 days. Policies automatically delete content upon expiry.
• archive Automatic archiving: Microsoft 365 Archive allows moving cold content to a more cost-effective storage tier within the SharePoint ecosystem itself. Archived data can be searched and recovered, but does not count the same way against the active storage quota.
• label Labelling and classification: use Microsoft Purview retention and sensitivity labels to automatically classify documents. A contract is labelled as "7-year retention", a draft as "Temporary 30 days". Automatic content-based classification (trainable classifiers) reduces reliance on users.
• cleaning_services Version cleanup: reduce the maximum number of versions to 50-100 in libraries with heavy editing. Run PowerShell scripts or use third-party tools to purge old versions in bulk. Microsoft has recently introduced the automatic version cleanup feature (version history limits) that facilitates this task.

SharePoint backup: why the recycle bin is not enough

One of the most common misconceptions about SharePoint Online is assuming that Microsoft protects user data. The reality is that Microsoft operates under a shared responsibility model: they guarantee infrastructure availability, but data protection is the organisation's responsibility.

The SharePoint recycle bin (first and second stage) retains deleted items for a maximum of 93 days. After that period, data is permanently lost. There is no historical restore point, no protection against malicious deletion by a disgruntled employee, and no coverage against data corruption from ransomware or a faulty sync.

A professional backup solution such as Veeam Backup for Microsoft 365 addresses these shortcomings:

• check_circle Unlimited retention: retains SharePoint, OneDrive, Exchange and Teams data for as long as the organisation requires, regardless of Microsoft's recycle bin limits.
• check_circle Granular restoration: recover an individual file, a complete folder or an entire SharePoint site to any point in time, without affecting the rest of the organisation.
• check_circle Ransomware protection: by storing backups outside Microsoft 365 in an independent repository, data remains protected even if the M365 admin account is compromised.
• check_circle Legal compliance: many regulations require retaining data for periods that exceed the 93-day recycle bin window. Veeam allows you to define retention policies that satisfy GDPR, ENS and sector-specific regulatory requirements.

Archiving alternatives: moving cold data to Object Storage S3

Not all SharePoint data needs to reside in active Microsoft 365 storage. Documents from completed projects, old meeting recordings, historical reports and obsolete list databases are perfect candidates for archiving to Object Storage S3.

Archiving to S3-compatible storage offers several advantages over keeping everything in SharePoint:

• savings Significantly lower cost: S3-compatible storage can cost a fraction of what Microsoft charges for additional SharePoint storage. With no egress fees and no per-API-request charges, long-term archiving is substantially more economical.
• lock Immutability and compliance: with Object Lock, archived data can be protected in WORM (Write Once Read Many) mode, ensuring that nobody can modify or delete it during the defined retention period. Ideal for regulatory compliance.
• public Data sovereignty: unlike Microsoft 365 storage, where geographic location depends on the tenant region, archiving to local Object Storage S3 guarantees that data remains in a specific data centre on Spanish soil.

The typical workflow involves using Veeam Backup for Microsoft 365 to export data from SharePoint sites that are no longer active, storing it in an S3 repository with a long-term retention policy, and then cleaning up the original SharePoint site to free space. If access to the archived data is needed in the future, it can be restored from the Veeam backup. Our managed services team can design and implement this workflow end to end.

Problems and solutions: practical summary

The following table summarises the main SharePoint storage challenges and the recommended solutions for each:

Conclusion

SharePoint is an extraordinarily powerful platform for document collaboration, but its ease of use has a side effect: storage grows silently and relentlessly. Without a clear governance strategy, organisations end up paying unnecessary licensing costs, suffering performance degradation and taking on compliance risks that could have been avoided.

• arrow_right Implement retention policies with Microsoft Purview to automate the cleanup of expired content.
• arrow_right Reduce the version limit to 50-100 and purge old versions periodically.
• arrow_right Deploy Veeam Backup for Microsoft 365 to ensure real protection of SharePoint, Teams and OneDrive data.
• arrow_right Archive cold data to Object Storage S3 to reduce costs and free up SharePoint space.
• arrow_right Regularly audit storage consumption and assign owners to each site to distribute responsibility.

If your organisation needs help controlling SharePoint growth, implementing Microsoft 365 backup or designing a long-term archiving strategy, our team is ready to help. Contact us for a no-obligation consultation.