Migrating from Google Workspace to Microsoft 365: Complete 2026 Guide

The 5 reasons we see in practice: (1) Word, Excel, PowerPoint desktop, Google Docs remains limited for advanced uses. (2) Defender Cybersecurity is far more mature than Google Workspace Standard. (3) Microsoft Teams dominates B2B (90% of Fortune 500), your clients ask you to join them on Teams. (4) Microsoft ERP/CRM, Dynamics 365 and Power BI integrate natively. (5) Similar total cost, Google Workspace Business Standard €12/u and Microsoft 365 Business Standard €12.50/u are nearly identical, but Microsoft 365 Premium (security included) is more profitable.

Gmail → Exchange Online: migration via Microsoft Migration Manager (free). All emails, folders, labels (transformed into folders), threads preserved. Time: 5-10 days depending on volume. Google Drive → OneDrive + SharePoint: Migration Manager also copies files preserving structure and permissions. Google Docs/Sheets/Slides are automatically converted. Calendar → Outlook: events, attendees, recurrences, attachments. Contacts: synchronized.

Total duration for a 50-user SMB: 4 to 6 weeks. Phase 1 (1 wk) audit + Microsoft 365 tenant + DNS. Phase 2 (2-3 wk) parallel Gmail/Exchange double-run (zero downtime). Phase 3 (1 wk) cutover + Google deactivation. Phase 4 (1 wk) Outlook/Teams/SharePoint user training. Helion Cloud integration cost: €4,500 to €8,000 for 50 users.

Pitfall 1: custom Google Sites, non-migratable, must be rebuilt in SharePoint. Pitfall 2: Google Forms tied to internal processes, recreate in Microsoft Forms or Power Apps. Pitfall 3: externally shared Google Drive links, audit and notify partners of new OneDrive/SharePoint URLs. Pitfall 4: third-party apps connected via Google OAuth, reconnect to Microsoft Graph. Pitfall 5: user resistance for the first 2 weeks, training and support are decisive.