Email is still the most business-critical tool for Swiss enterprises – and a move to Exchange Online is the most common entry point into Microsoft 365. This guide shows Swiss SMBs and enterprises how to plan and run an Exchange Online migration in 2026 – whether you are coming from on-prem Exchange Server, Google Workspace or a hosted Exchange provider.

Why move to Exchange Online now?

Mainstream support for Exchange Server 2019 ended in late 2025; Exchange Server Subscription Edition is available but no longer economical for most Swiss SMBs. Reasons to move to Exchange Online:

• Swiss data residency (Zurich / Geneva) and EU Data Boundary
• Lower TCO (no servers, no patching, no backup tape library)
• Native integration with Microsoft Teams, SharePoint, Microsoft Purview and Microsoft 365 Copilot
• Microsoft Defender for Office 365 for anti-phishing and anti-malware
• Mailbox sizes from 50 GB to 100 GB per user

Which migration strategy fits your organisation?

For most Swiss SMBs with 30–200 employees, cutover or Modern Hybrid express migration is the pragmatic path.

The seven phases of an Exchange Online migration

1. Discovery and assessment (1–2 weeks)

• Inventory of all mailboxes (user, shared, resource, distribution lists, public folders)
• Mailbox sizes, attachment patterns, retention
• Mailflow analysis (MX records, SPF, DKIM, DMARC, anti-spam gateway like Hornetsecurity or Proofpoint)
• Third-party systems sending SMTP (ERPs like Bexio/Abacus, scanners, IoT, newsletter tools)
• Mobile devices (ActiveSync, OWA, Outlook for iOS/Android)

2. Tenant preparation (1 week)

• Microsoft 365 tenant with default region Switzerland for Swiss data centres
• Verify and configure domains (TXT, MX, Autodiscover, SPF, DKIM, DMARC)
• Prepare licences (Business Standard, Premium or E3/E5)
• Microsoft Entra ID hardening and Conditional Access
• Microsoft Defender for Office 365 policies (Safe Links, Safe Attachments, anti-phishing)

3. Identity and sync (1–2 weeks)

• Entra Connect / Cloud Sync for hybrid identities
• Optional: Pass-Through Authentication or Password Hash Sync
• Enforce multi-factor authentication (MFA) for all users
• Privileged Identity Management (PIM) for admin roles

4. Pilot migration (1–2 weeks)

• 5–15 pilot mailboxes from IT, leadership and a pilot department
• Test Outlook profiles, mobile devices, signatures
• Document results and refine the runbook

5. Wave planning and bulk migration (2–8 weeks)

• Migration in waves of 50–150 mailboxes (typically over weekends)
• Tooling: Exchange Online migration endpoints, BitTitan MigrationWiz or Quadrotech
• Communication to employees (what changes? maintenance windows?)
• Monitor throttling, bandwidth and error reports

6. Cutover and mailflow switch (one weekend)

• Switch MX records to Exchange Online (or mail gateway)
• Reconfigure anti-spam gateway (or replace with Defender for Office 365)
• Move third-party systems to SMTP AUTH or High Volume Email for M365
• Test all inbound and outbound scenarios

7. Post-migration and cleanup (2–4 weeks)

• Migrate public folders to Microsoft 365 Groups or SharePoint
• Decommission legacy Exchange servers (cleanly remove Hybrid Configuration)
• Configure retention policies and Litigation Hold (Swiss Code of Obligations Art. 958f, FADP)
• Set up backup with Microsoft 365 Backup, Veeam or mount10
• Train users on Outlook on the Web, Outlook New and mobile

Migration from Google Workspace to Exchange Online

A common scenario for Swiss start-ups and subsidiaries of international groups:

• Google Workspace connector (native in Exchange Online) for mailflow coexistence
• Migrate mail, calendar and contacts via the Google Workspace (Gmail) migration endpoint
• Drive-to-OneDrive migration in parallel using Mover.io or ShareGate
• Move Google Groups to Microsoft 365 Groups
• DNS switch and training Outlook / Teams instead of Gmail / Meet

Migration from hosted Exchange (Swiss provider, GoDaddy, Rackspace, etc.)

• IMAP migration for content
• PST export/import for historical data
• For Swiss providers: direct cutover often possible
• Note: calendars and contacts must be exported separately

Data residency and FADP compliance

Critical for Swiss enterprises:

• Choose default region Switzerland at tenant setup so Exchange mailboxes live in Zurich / Geneva
• Review and store the data processing agreement (DPA) with Microsoft
• Enable Microsoft Purview sensitivity labels and DLP for email (e.g. protection of Swiss social security numbers, IBAN, credit cards)
• Retention policies aligned with Swiss Code of Obligations Art. 958f (10 years business correspondence)
• Document the processing register per FADP Art. 12

FAQ

How long does an Exchange Online migration take for a Swiss SMB with 80 users? Typically 6–10 weeks end-to-end: 2 weeks discovery, 1 week tenant setup, 1 week pilot, 2–4 weeks wave migration, 1–2 weeks cleanup.

Can we keep working during the migration? Yes. With hybrid or cutover migrations over weekends, email remains continuously available. Per-mailbox downtime is limited to a few minutes.

What happens to public folders? Public folders are either migrated to Exchange Online or moved to SharePoint Online or Microsoft 365 Groups – usually the more sustainable option.

Do we need an extra backup during the migration? We recommend a snapshot backup before cutover. After cutover, set up an ongoing Microsoft 365 Backup (native, Veeam or mount10).

What does an Exchange Online migration with CNEXT cost? Discovery from CHF 5,000, pilot migration from CHF 8,000, full migration for an 80-user SMB typically CHF 25,000–45,000 including training. Enterprise hybrid projects are scoped individually.

Conclusion

Migrating to Exchange Online is the standard move for Swiss enterprises in 2026 – whether it is the entry point to Microsoft 365 or the retirement of the last on-prem Exchange Server. CNEXT, a Microsoft Solutions Partner in Bern, delivers cutover, staged, hybrid and Google Workspace migrations in full compliance with FADP and GDPR.