Office 365 and Microsoft 365 Migration Cost UK: 2026 Pricing Guide

When a UK business owner or finance director starts planning a move to Microsoft 365, the first question is almost always the same: "Am I looking at hundreds, thousands, or tens of thousands of pounds?"

If you ask three different IT providers, you will often receive three wildly different quotes. One claims they can move your entire business over a weekend for £1,500. Another quotes £18,000 for what sounds like the same project. A third gives you a vague daily rate and refuses to commit to a fixed cost for the project.

How Much Does an Office 365 Migration Cost in the UK?

In the UK, a straightforward Office 365 migration for a small business usually starts from around £1,500 to £4,000. Medium-sized migrations involving 25 to 100 users typically range from £4,000 to £12,000. More complex projects involving Exchange hybrid, tenant-to-tenant migration, SharePoint, Teams, OneDrive, public folders or file server migration can range from £8,000 to £30,000+. Although Microsoft now uses the name Microsoft 365, many businesses still search for Office 365 migration costs. In practical terms, most people are asking the same question: how much will it cost to move email, files, users and security into Microsoft 365 properly?

With over 25 years of hands-on Microsoft 365 and Exchange experience, we have delivered migrations from 10-user startups to 5,000+ user organisations. The figures in this guide reflect what we actually see in real UK projects, not theoretical estimates.

This confusion happens because "migration" can mean two completely different things. A simple mailbox copy from basic hosted email is a quick job. A full engineering project involving legacy Exchange servers, public folders, years of file share clutter, custom SharePoint permissions, and strict security requirements is a serious technical engagement. User count alone tells you very little about what the work will actually entail.

In this guide, we break down realistic UK migration cost ranges for 2026, explain the hidden expenses that catch businesses off guard, and show you how to evaluate quotes so you can secure an accurate, fixed-price agreement for your organisation.

Typical Microsoft 365 Migration Cost Ranges in the UK

To help you benchmark your budget, the table below outlines typical project cost ranges across common migration scenarios in the UK market. These figures represent one-off consulting and engineering fees to plan, execute, and deliver the technical transition properly.

Office 365 vs Microsoft 365: Why We Use Both Terms

Microsoft now generally uses the name Microsoft 365, but many UK businesses still search for Office 365 migration, Office 365 migration cost and Office 365 migration services. For most SME migration projects, the search intent is the same. Businesses want to move email, calendars, files, Teams, users and security into Microsoft's cloud platform. Throughout this guide, we use both Office 365 and Microsoft 365 where helpful because clients still use both terms when describing the same project.

These figures are illustrative and based on typical UK migration projects. Actual costs depend on mailbox volumes, SharePoint data, hybrid complexity, coexistence requirements and user numbers.

Real-World Migration Examples

To give you a better sense of how these ranges apply in practice, here are three typical scenarios based on recent UK projects:

These are illustrative examples. Your project may be simpler or more complex depending on your specific environment.

When you look at these pricing bands, keep in mind that they cover the technical migration effort itself. They do not include your monthly Microsoft subscription licences or optional third-party add-ons, which we cover later in this guide. A small business with 15 users moving plain email might land near the bottom of the first bracket. If that same 15-user company also has 800 GB of legacy file shares, custom access permissions, and mobile device management requirements, the engineering hours increase accordingly.

What Will Influence Your Migration Cost?

Every environment is unique, but certain technical factors reliably push a project toward the higher end of the pricing spectrum. Use this checklist to gauge your project complexity:

The more of these that apply to your environment, the more likely your project sits toward the upper end of the pricing ranges above.

What Factors Actually Drive the Migration Cost?

When we assess a new environment at EJK Consultancy, we look far beyond how many staff work at the company. Seven core technical and operational factors determine the real workload and price of your migration project.

1. Mailbox Count and Total Data Volume

Moving twenty 2 GB mailboxes is fast and straightforward. Moving twenty 80 GB mailboxes with decade-old archives and thousands of nested folders takes significantly more sync time, throttling management, and verification. High data volume requires staged pre-synchronisation passes to ensure the final cutover window runs smoothly without dropped connections or lost messages.

2. Source Platform and Hybrid Coexistence

Migrating from basic IMAP or Google Workspace is fundamentally different from moving off an old on-premises Microsoft Exchange server. If your business relies on Exchange public folders, complex mail routing, or legacy Active Directory synchronisation, a simple cutover migration is rarely suitable. You will need a hybrid coexistence model where old and new environments work side-by-side during the transition, which increases project design, network testing, and engineering hours.

3. SharePoint and File Share Scope

Moving email is relatively clean. Moving company files is where most projects become complicated. If you simply copy a chaotic on-premises file server straight into SharePoint Online, your staff will struggle with broken links, sync errors, and unmanageable permissions.

A proper SharePoint migration project involves auditing existing folder structures, flattening deep directory paths, removing invalid characters, establishing clear site governance, and mapping legacy NTFS permissions to modern Microsoft 365 Groups. That planning work takes time, but it prevents costly file management problems later.

4. Data Cleanup and Pre-Migration Remediation

If your current systems contain 15 years of duplicate files, orphaned user accounts, and unmapped shared mailboxes, someone has to clean them up before data movement begins. You can either pay your internal team to rationalise your data before the project, or engage your migration partner to audit and remediate it for you. Skipping cleanup entirely means paying to migrate digital noise into your cloud environment.

5. Third-Party Tooling and Software Licences

Specialist migration platforms such as BitTitan MigrationWiz, Quest, or SkyKick charge per-mailbox or per-workload licence fees. While native tools provided directly by Microsoft work well for standard scenarios, complex tenant-to-tenant or multi-source migrations often require specialised third-party tools to preserve metadata, file timestamps, and granular permissions accurately.

6. Security and Identity Baseline

A migration is the single best moment to secure your Microsoft 365 tenant properly. Standard project scope should include configuring Entra ID identity policies, multi-factor authentication (MFA), Conditional Access rules, and Microsoft Defender baselines. If a quote covers only copying data without locking down admin roles or securing mobile access, your business remains exposed to cyber risks.

7. User Training and Post-Migration Support

Technical cutover is only half the job. If your employees arrive on Monday morning unable to locate shared files, send from alias addresses, or log into Teams on their phones, business productivity grinds to a halt. High-quality migration projects allocate dedicated hours for staff quick-start guides, admin handover, and on-hand support desk assistance during the first week after cutover.

Hidden Costs That Catch UK Businesses Off Guard

Beyond the primary consulting fee, several hidden or ongoing expenses frequently surprise finance directors who have not reviewed the full project picture.

Ongoing Microsoft 365 Subscription Licences

Project implementation fees do not include your monthly or annual Microsoft 365 licence costs. For a typical UK SME, core user licences fall into three main tiers:

• Microsoft 365 Business Basic: Web and mobile apps plus email, OneDrive, and Teams. Ideal for deskless staff or light email users.
• Microsoft 365 Business Standard: Full desktop Office apps plus complete cloud services. The standard choice for most office workers.
• Microsoft 365 Business Premium: Desktop apps, advanced security, Conditional Access, and Intune device management. Essential for businesses wanting strong cybersecurity.

Always verify exact current pricing directly with Microsoft or your cloud solution provider before finalising annual IT budgets, as licence fees are billed separately from consulting charges. You can review official feature documentation on Microsoft Learn to ensure your chosen tier matches your compliance requirements.

Dual Licensing During Coexistence

During a phased or hybrid migration, you will briefly pay for both your legacy host (such as Google Workspace or hosted Exchange) and your new Microsoft 365 licences while data synchronises. Factor two to four weeks of licence overlap into your cash flow forecast so you are not caught off guard by double billing during the cutover month.

Third-Party Cloud Backup

Microsoft operates a highly resilient infrastructure, but Microsoft 365 is not an independent backup service. If an employee permanently deletes critical files or ransomware encrypts a shared folder, native retention bins have strict limits. Independent cloud-to-cloud backup typically adds £1.50 to £4.50 per user per month, and should be factored into your operational running costs from day one.

DNS, Mail Relays, and Line-of-Business Apps

Printers, photocopiers, scanners, ERP software, and CRM platforms often send transactional emails through your old mail server. Discovering and reconfiguring these application SMTP relays during cutover requires technical investigation. Furthermore, updating public DNS records (SPF, DKIM, and DMARC) is essential to prevent your legitimate business emails from ending up in customer spam folders after cutover.

Why the Cheapest Quote Is Rarely the Best Value

It is tempting to pick the lowest fixed quote, but ultra-cheap migration proposals usually rely on dangerous technical shortcuts that cost significantly more in the long run:

• No pre-migration discovery: The provider moves data blind without checking mailbox sizes or app dependencies, causing unexpected failures during cutover weekend.
• Lift-and-shift file dumping: On-premises file servers are dumped into a single giant SharePoint folder, creating sync errors, broken file links, and permission leaks across departments.
• Skipped security baselines: User accounts are left without MFA or Conditional Access, leaving your company vulnerable to immediate credential theft and email compromise.
• Zero post-migration support: The IT company marks the ticket closed at 9:00 AM on Monday, leaving your staff to struggle alone with broken Outlook profiles and mobile sign-in errors.

When a cheap migration goes wrong, the cost of emergency remediation, business downtime, and lost billable hours quickly dwarfs whatever money you saved on the initial quote. A finance director reading this should treat migration as an investment in business continuity and long-term efficiency, not a low-grade commodity purchase.

How to Get an Accurate, Fixed-Price Migration Quote

To avoid surprise bills and unexpected scope changes, demand a clear statement of work from your consultancy before signing any contract. A thorough proposal should clearly itemise every technical workstream and deliverable:

• Exact source platforms, mailbox numbers, and file storage volumes included in scope.
• Specific treatment of file permissions, shared mailboxes, distribution lists, and public folders.
• Security baseline settings, including MFA enrolment, Conditional Access policies, and admin governance.
• Cutover timeline, out-of-hours deployment details, user communication plans, and hypercare support duration.

At EJK Consultancy, we believe in total transparency. Whether you are planning an Exchange to Microsoft 365 migration or switching over from Google Workspace to Microsoft 365, we assess your source environment thoroughly before writing a single line of scope. That way, you receive a guaranteed fixed price with zero surprises.

Frequently Asked Questions

Frequently Asked Questions About Office 365 Migration Costs