Deciding where your business files should live is one of the more consequential IT choices you will make. For years the answer was simple: a network file server sitting in the office, mapped as a drive letter on every PC. Today most UK businesses run Microsoft 365, which brings SharePoint Online and OneDrive into the picture and raises an obvious question — do you still need that file server at all? This guide compares the two approaches honestly, so you can pick the right home for your data based on how your team actually works, not on habit or hype.
The two models in plain terms
A network file server is a physical or virtual machine on your local network holding shared folders. Staff access files through mapped drives (the familiar S: or H:), permissions are set with NTFS and Active Directory groups, and everything lives within the four walls of your office (or a data centre you connect to over VPN). It is fast on the local network, gives you full control, and behaves exactly as people expect.
SharePoint Online is a cloud service within Microsoft 365. Files live in document libraries inside SharePoint sites, which usually map to teams or projects, and are surfaced through Microsoft Teams, the web browser and File Explorer via OneDrive sync. There is no server to patch, storage scales on demand, and access works from anywhere without a VPN.
Neither is universally 'better'. The right choice depends on where your people work, the size and type of your files, your compliance needs and your appetite for managing infrastructure. Many organisations end up with a hybrid for a transitional period.
Access and remote working
This is where the models diverge most sharply. A file server was designed for people sitting in one building on one LAN. Remote access typically relies on a VPN, which can be slow for large files and adds a support burden. If your workforce is hybrid or field-based, mapped drives over VPN are a common source of frustration and helpdesk tickets.
SharePoint was built for distributed working. Staff open files in a browser, in Teams or through synced folders on their device, with no VPN required. Co-authoring lets several people edit the same Word or Excel document at once, and version history is automatic. For businesses that adopted flexible working, this alone often justifies the move.
The trade-off is that SharePoint depends entirely on your internet connection. If your line is slow or unreliable, cloud file access suffers. This is why we usually pair a SharePoint migration with a proper connectivity review — a leased line or resilient backup connectivity makes cloud working dependable rather than a daily gamble.
Security and compliance
A file server keeps data physically under your control, which some regulated firms find reassuring. But that control cuts both ways: patching, ransomware protection, backup integrity and physical security are all your responsibility. A single compromised admin account or an unpatched vulnerability can encrypt the entire share.
SharePoint Online inherits Microsoft 365's security stack — conditional access, multi-factor authentication, data loss prevention, retention policies and audit logging. Files are encrypted at rest and in transit, and granular sharing controls let you decide exactly who can access what, internally and externally. Layering identity protection and strong email security on top closes the most common attack routes.
Whichever model you choose, sensible access controls and monitoring matter. We often recommend endpoint security (EDR) across all devices, because ransomware frequently reaches file storage through a compromised laptop rather than the server itself.
- File server: full physical control, but you own all patching, backup and ransomware risk
- SharePoint: built-in encryption, MFA, DLP and audit trails via Microsoft 365
- External sharing is easy and controllable in SharePoint; awkward and risky on a file server
- Both benefit from strong identity and endpoint controls
Performance and file types
File servers win on raw local speed and on certain workloads. Very large files, design and CAD applications, database files and anything opened directly from a mapped drive tend to perform better on a LAN. Applications that expect a traditional file path can also misbehave when pointed at synced cloud folders.
SharePoint handles Office documents, PDFs and general business files superbly, but it is not ideal for enormous media libraries, files that change constantly through an application, or datasets with very deep folder structures. There are practical limits per file and per library that catch people out during a rushed migration.
In short: if your work is mostly Word, Excel, PowerPoint, PDFs and shared project folders, SharePoint fits naturally. If you rely on specialist software writing to file paths, keep those workloads on a server or on dedicated storage and move only what genuinely benefits.
Cost: capital, licensing and hidden effort
A file server carries capital and ongoing costs that are easy to underestimate. There is the hardware itself, Windows Server licensing, the replacement cycle every few years, electricity, backup software and the staff time to patch and maintain it. When the hardware ages or fails, you face an unplanned refresh project.
SharePoint Online is included in most Microsoft 365 business and enterprise plans, so many organisations already pay for it. Storage is generous and predictable, there is no hardware to replace, and Microsoft handles maintenance and resilience. The cost shifts from lumpy capital spend to a steady per-user subscription.
The honest caveat is migration effort. Moving years of accumulated folders — often with messy permissions and duplicate files — takes planning and is rarely a simple copy. Budget for a proper Microsoft 365 migration rather than treating it as an afternoon job, and use it as a chance to tidy up structure and retention.
Backup and business continuity
A common misconception is that cloud data does not need backing up. Microsoft protects its infrastructure and offers limited retention, but it operates a shared-responsibility model: your data is your responsibility. Accidental deletion, malicious insiders and ransomware syncing to the cloud are all real risks that native retention will not fully cover.
With a file server, backup is entirely on you — and it must be tested. Too many businesses discover their backups were incomplete only when they need them. Whichever platform holds your files, a dedicated cloud backup solution with sensible retention and periodic restore tests is essential.
Continuity also depends on access. A file server going offline stops work for the whole office; a SharePoint outage or an internet failure does the same for cloud files. Resilience planning — redundant hardware or redundant connectivity — should match how critical the data is to daily operations.
When to choose which — and the hybrid middle ground
Choose SharePoint Online if your team works flexibly, collaborates heavily on Office documents, wants version history and co-authoring, and you would rather not own and maintain server hardware. For most professional services, charities and office-based SMEs, it is now the default sensible choice.
Keep a file server (or add cloud file services like Azure Files) if you run applications that demand local file paths, work with very large media or CAD files, or have connectivity constraints that make cloud access impractical. Some firms also retain a server for specific regulated archives.
A hybrid is often the pragmatic answer during transition: move collaborative documents to SharePoint while leaving specialist workloads on a server, then revisit as connectivity and applications evolve. Our SharePoint consultancy and co-managed IT support teams regularly design this kind of staged approach so nothing breaks and staff are not left confused about where files belong.
Making the move without disruption
The success of any file migration lives in the preparation. Audit what you actually have, identify stale data you can archive rather than migrate, and map your existing permissions to a cleaner SharePoint site and library structure. Poorly planned permissions are the single biggest cause of post-migration complaints.
Communicate clearly with staff and provide short, practical guidance on where files now live and how to sync them. A well-run cutover, often over a weekend, keeps disruption minimal. Plan the IT project delivery so testing, a pilot group and a rollback option are all in place before you switch everyone over.
If you are weighing this up and want a straightforward assessment of your current setup, get in touch. We will look at how your team works, your connectivity and your data, then recommend the option that reduces friction rather than adding it.