The True Cost of Migrating from Microsoft 365 to Nextcloud: A Detailed Breakdown

Nextcloud is the most frequently cited European alternative to Microsoft 365 for file storage and collaboration. It is open source, German-founded, self-hostable, and available through dozens of EU hosting providers. For organisations evaluating a move away from Microsoft, it is usually the first name on the list.

But “migrate to Nextcloud” is not a plan. It is a destination. The plan requires understanding what the migration actually involves, what it costs, what it does not replace, and where the surprises are. This post breaks down the true cost for a specific scenario: a 25-person European professional services firm migrating from Microsoft 365 Business Premium to a Nextcloud-centred stack.

The Starting Point

Our reference organisation:

• 25 employees across two offices (Netherlands and Germany)
• Microsoft 365 Business Premium (€20.60/user/month as of early 2026)
• Azure AD (Entra ID) for identity and SSO
• Exchange Online for email
• SharePoint Online and OneDrive for file storage (~500 GB total)
• Microsoft Teams for internal communication
• 12 third-party applications connected via Azure AD SSO
• 8 Power Automate flows (approval workflows, notification triggers, data sync)
• Intune for device management (25 laptops, mix of Windows and macOS)
• No self-hosted infrastructure currently

Current annual Microsoft 365 cost: 25 users x €20.60/month x 12 = €6,180/year

What Nextcloud Replaces (and What It Does Not)

Nextcloud covers a subset of the Microsoft 365 stack:

Nextcloud replaces the file storage and basic collaboration layer. Email, identity, device management, and workflow automation require separate solutions.

The Target Stack

For a complete Microsoft 365 replacement, the target stack for our reference organisation:

Cost Breakdown: Migration

1. Infrastructure Setup

Setting up the target stack on EU infrastructure:

Compared to current Microsoft 365 cost of €6,180/year, the infrastructure cost is lower. But infrastructure is only part of the picture.

2. Migration Labour

This is where the real cost sits. Migration labour for a 25-person organisation:

At an internal resource rate (if your IT team does it), the cost is lower in cash but higher in opportunity cost. At a consultancy rate of €120 to €180 per hour, the range is €27,840 to €41,760.

3. Costs Nobody Budgets For

Every migration has costs that do not appear in the initial plan:

Productivity loss during transition. Even with parallel running, employees will be slower during the transition period. Estimate 10 to 20 percent productivity loss for 2 to 4 weeks across all 25 employees. At an average fully loaded cost of €60/hour: 25 employees x 8 hours/day x 15 days x 15% loss x €60 = €27,000 in lost productivity.

Edge cases. The file migration tool handles 95% of files cleanly. The remaining 5% have special characters in filenames, deeply nested folder structures, or file sizes that exceed Nextcloud’s default upload limit. Finding and fixing these takes 10 to 20 hours of unplanned work.

Integrations that break. Some third-party tools have deeper Microsoft dependencies than expected. A CRM that syncs contacts via Microsoft Graph API, or a project management tool that embeds SharePoint files, requires additional migration work that the initial audit did not fully capture.

User resistance. Some employees will prefer the old tools. Change management requires patience, follow-up training, and sometimes compromises (e.g., allowing certain tools to remain during a transition period).

Google Docs / Microsoft formats. If your organisation created documents natively in Google Docs or Word Online, the exported files may have formatting issues when opened in Nextcloud Office or ONLYOFFICE. Budget time for checking and fixing critical documents.

4. Ongoing Operational Costs

After migration, the new stack requires ongoing maintenance:

If you use a managed Nextcloud provider instead of self-hosting, the maintenance labour cost drops significantly, but the infrastructure cost increases. Managed Nextcloud hosting for 25 users with 1 TB storage typically costs €300 to €600/month from EU providers.

Total Cost Summary

The uncomfortable truth: migrating from Microsoft 365 to a self-hosted European stack is more expensive in direct costs for most organisations with 25 or fewer employees. The Microsoft 365 licence is subsidised by Microsoft’s scale. The European alternative stack requires more operational labour.

When the Migration Makes Financial Sense

The financial case for migration depends on factors beyond direct licensing costs:

Regulatory compliance costs. If NIS2 or DORA require documented exit strategies, concentration risk assessments, and regular testing, the cost of maintaining compliance while staying on Microsoft can approach or exceed the migration cost. The exit strategy itself requires investment whether you migrate or not.

Microsoft price increases. Microsoft has increased Microsoft 365 prices repeatedly (the March 2022 increase was 15 to 25 percent for most plans). If prices continue to rise, the cost crossover point moves forward.

Risk reduction value. The migration eliminates CLOUD Act jurisdictional exposure, reduces concentration risk, and provides operational independence. Assigning a monetary value to risk reduction is difficult, but for regulated organisations, the cost of a regulatory finding related to third-party concentration risk could dwarf the migration cost.

Insurance premiums. Some cyber insurance providers are beginning to differentiate premiums based on cloud provider concentration risk. Diversification may reduce premiums.

When Migration Does Not Make Financial Sense

For some organisations, the honest answer is that migration is not the right move, at least not now:

• Organisations with fewer than 10 employees where the operational overhead of self-hosting exceeds the licence savings
• Organisations where Microsoft-specific features (Power BI, Dynamics 365 integration, advanced Intune policies) are genuinely critical to operations
• Organisations without internal IT capacity or budget for external IT support to maintain the new stack
• Organisations in the middle of a contract term with steep early termination penalties

For these organisations, a dependency audit still provides value. Understanding what you depend on, even if you choose to keep the dependency, is the first step toward managing it.

The Middle Path

Many organisations choose a partial migration that addresses the highest-risk dependencies without a full platform switch:

1. Move DNS to a European provider. Immediate risk reduction, minimal cost. Same day.
2. Deploy Keycloak alongside Azure AD. Run identity in parallel. If Azure AD becomes unavailable, Keycloak takes over. Cost: €2,000 to €5,000 setup, €120/month ongoing.
3. Back up email and files to EU-hosted storage. Use a third-party backup tool (Veeam, Afi, or open-source alternatives) to maintain a copy of your data outside Microsoft’s control. Cost: €500 to €1,500/year.
4. Move email to Proton. The highest-value, most achievable single migration. Cost: ~€5,000 migration labour + €200/month ongoing.
5. Keep Teams and SharePoint for now. Accept the dependency with documentation, and revisit when contracts renew.

This partial approach costs €10,000 to €15,000 and addresses the most critical risks (identity, email, backup) without the full cost and disruption of a complete platform migration.

The Real Question

The true cost of migrating from Microsoft 365 to Nextcloud is not primarily a financial calculation. It is a question about what kind of risk your organisation is willing to carry.

Staying on Microsoft 365 is cheaper in direct costs. It carries jurisdictional risk, concentration risk, and a dependency on a foreign legal framework over which European organisations have no control.

Migrating to a European stack is more expensive in direct costs. It provides operational independence, regulatory alignment, and control over your own infrastructure.

Both choices have costs. The dependency audit helps you understand which costs you are already paying and which costs you are choosing.

Sovereign Shift delivers the complete cost picture before you commit: dependency map, replacement shortlist, and migration roadmap with realistic estimates for your specific stack. See pricing →