The honest answer is: it depends. But "it depends" isn't useful if you're trying to build a budget. In this article we break down all the costs of a Microsoft 365 migration — licenses, consulting, tools, training, hidden risks — with concrete figures for three typical tenant sizes.
What drives the cost of an M365 migration
Before the numbers, the variables. The cost of a Microsoft 365 migration depends on four main factors:
- Where you're migrating from: Google Workspace, on-premises Exchange, a generic IMAP host, or a mix. Each scenario has a different complexity profile.
- How much data needs to move: email only, or also calendar, contacts, Drive/file share. Email is the simplest; Drive to SharePoint is the most labour-intensive.
- How many users: 10 users and 100 users are handled very differently. Above 50 users the tooling, timelines and training budgets all change.
- How "clean" the source environment is: a well-documented Google tenant with clear roles is one thing. An on-premises Exchange installed ten years ago by a consultant who's unreachable is another.
Cost 1: Microsoft 365 licenses
This is the most visible cost — and often the one that gets all the attention, to the detriment of everything else. Microsoft 365 Business licenses are charged per user per month.
| Plan | Price/user/month (excl. VAT) | Includes | Best for |
|---|---|---|---|
| Business Basic | €6.07 | Exchange Online, Teams, SharePoint (web only) | Users who work entirely in the browser |
| Business Standard | €12.13 | Everything in Basic + desktop apps (Word, Excel, Outlook) | Most SMBs |
| Business Premium | €27.73 | Everything in Standard + Intune, Defender, Azure AD P1 | Organisations with advanced security requirements |
The prices above are current Microsoft list prices as of July 2026. Purchasing through a CSP reseller like Elethos doesn't change the price — the list is fixed. What changes is the support: you have a partner who knows your tenant, can intervene directly, and is accountable for how it's configured.
The difference between Basic (€1,457/year for 20 users) and Premium (€6,655/year) is almost €5,200 per year. Before choosing, a licensing audit clarifies which plan you actually need — Business Standard covers ~80% of cases.
Cost 2: technical consulting
This is the most variable cost — and the one that makes the biggest difference to the outcome. A poorly executed migration has hidden costs that far exceed any savings on consulting fees.
The main drivers of consulting cost are three: the complexity of the source environment, the volume of data to migrate, and the number of users to manage. There's also a fourth driver that many underestimate: documentation. A poorly documented tenant requires an inventory phase before the migration even starts — and that time is billable.
- 5–20 users
- Documented environment
- No specific complexity
- 20–50 users
- Full data migration
- Some legacy (rules, aliases, shared mailboxes)
- 50+ users
- File share / SharePoint migration
- Hybrid or legacy environment
These figures include the technical phase: planning, data migration, M365 tenant configuration, DNS cutover, mailflow and post-migration verification. They do not include user training.
Cost 3: migration tools
This is where one of the most common budget surprises hides. Email migration is free — Exchange Online includes a native migration engine. But calendar, contacts and especially file migration are not.
Email migration: included in M365
The Exchange Admin Center includes a native IMAP migration engine, free to use, that works well for email from Google Workspace, generic IMAP and Hosted Exchange. It handles up to 500 mailboxes, migrates email only, and has no additional cost beyond the M365 license.
Full migration: third-party tools
If you also need to migrate calendar, contacts and Google Drive, you'll need dedicated tools:
| Tool | Indicative cost | What it migrates | Best for |
|---|---|---|---|
| BitTitan MigrationWiz | €15–25/mailbox | Email, calendar, contacts, Drive → OneDrive/SharePoint | The most widely used choice for SMBs |
| Cloudiway | €12–20/user | Email, calendar, contacts, Drive, Teams | Tenants above 50 users |
| SPMT (Microsoft) | Free | Local file share → SharePoint/OneDrive | File migration from local folders |
For a 20-user organisation using MigrationWiz, tool costs are approximately €300–€500 — not a huge figure, but frequently forgotten in initial budgets.
Cost 4: training and change management
The most underestimated cost — and the one that determines whether the migration is considered a success by the people who actually use it.
Switching email, calendar and file sharing tools is a significant operational change. Outlook is not Gmail. Teams is not Google Meet. SharePoint is not Google Drive. Users who don't receive training either revert to what they know — or lose weeks of productivity.
- Group onboarding session (2–3 hours, all key features): €400–€800 per session, up to 20–25 participants.
- Individual sessions for key users (IT leads, delegated admins): €150–€300/hour.
- Support materials (quick-reference guides, internal FAQ): often included in a structured consulting package.
- Post-migration support (first 2–4 weeks): €50–€150/hour on demand, or included in an ongoing support contract.
For most SMBs with 10–30 users, one onboarding session plus a few hours of post-migration support is sufficient. Indicative budget: €800–€1,500.
Hidden costs: the ones nobody budgets
These don't appear in standard quotes — but they're real, and they can be significant.
If the migration takes two or three weeks, you'll have a period where you're paying for both Google Workspace and M365 licenses. For 20 users on Business Standard, that's around €250 of overlap — not a lot, but almost always forgotten.
A 3-hour training session for 20 people is 60 hours of stopped productivity. If your average staff cost is €30/hour, that's €1,800 in lost output — plus the ramp-up time over the following weeks. It's not a cost you pay to a vendor, but it's a real cost to the organisation.
This is the highest cost. A rushed DNS cutover that breaks mailflow for 24 hours can mean days of lost commercial email. A migration without SPF/DKIM/DMARC lands your messages in spam for months. A M365 tenant handed over without documentation becomes technical debt you pay every time you change providers. Saving money on proper consulting almost always costs more in the end.
A migration to M365 without a security baseline (MFA, Conditional Access, audit logs) leaves the tenant exposed. A single compromised account in a 20-person company has an average remediation cost of €5,000–€20,000 according to cyber insurance data. Including security configuration in the migration is far cheaper.
Budget table by tenant size
Summary of total costs for three typical scenarios. Figures exclude recurring M365 license costs.
| Scenario | Users | From | What migrates | Total budget |
|---|---|---|---|---|
| Basic migration | 5–15 | Google Workspace or IMAP | Email only | €800 – €1,500 |
| Full SMB migration | 15–30 | Google Workspace | Email + calendar + contacts + Drive | €2,500 – €5,000 |
| Exchange on-premises migration | 20–50 | Exchange Server | Email + mailboxes + file share | €4,000 – €10,000 |
These ranges include consulting, migration tools and one training session. They exclude recurring M365 licenses, additional security tooling and post-migration support beyond the first few weeks.