Moving from Google Workspace to Microsoft 365

Why businesses make the move

The usual reasons are practical. The business has grown into needing desktop Word and Excel for client work, a key software package integrates better with Microsoft 365, or the team wants Teams calling, SharePoint and the device management that comes with Microsoft's business plans. Sometimes a merger or a new owner simply standardises on Microsoft.

Be clear about the reason, because it shapes the project. If desktop Office is the main driver, licensing and file migration matter most. If security and device management are the driver, Intune enrolment and sign-in policies should be part of the plan from day one rather than a later phase that never happens. Check current Microsoft 365 pricing for the plan you need before committing.

Mail, calendars and contacts

Microsoft's built-in migration for Google Workspace moves email, calendar and contacts from each Gmail account into the matching Exchange Online mailbox. Third-party migration services do the same with extra reporting, scheduling and support for less common items. Either way, you set up the Microsoft 365 users first, connect the migration tool to Google with an admin-approved service account, then start copying.

A first pass copies the bulk of the history while staff keep working in Gmail. Labels become folders, which means an email with several labels can appear in several folders. Very large mailboxes take longer, and some items, such as Google Chat history and certain calendar features, do not come across. Tell staff what will and will not move before they discover it themselves.

Drive files

Each person's My Drive usually goes to their OneDrive, and Shared Drives go to SharePoint libraries. Microsoft offers a free migration tool for Google Drive, and third-party tools cover it too. Google Docs, Sheets and Slides are converted to Word, Excel and PowerPoint during the copy. Most convert well, but complex spreadsheets with Google-specific formulas, scripts or add-ons need checking afterwards.

Sharing does not carry over perfectly. Files shared with specific colleagues generally keep that access if the users are mapped correctly, but links shared with outsiders do not survive, and anything shared as anyone with the link needs to be shared again from the new location. Use the move as a chance to tidy, rather than copying ten years of unused files.

Cutover: changing where mail goes

Your domain's MX records tell the internet where to deliver email. At cutover you change them from Google to Microsoft, after which new mail arrives in Microsoft 365. Lower the time-to-live on the DNS records a day or two before so the change takes effect quickly. Do it at a quiet time, usually a Friday evening, then run a final incremental migration pass to pick up mail that arrived in Gmail during the switch.

Update the other records at the same time: SPF to include Microsoft, DKIM signing in Microsoft 365 and your DMARC policy. Missing or stale records are a common reason for mail going to junk after a migration. Leave Google Workspace running for a few weeks with limited access in case something was missed, then cancel it once you are sure.

The pieces people forget

Google Forms, Sites, Apps Script automation and third-party apps that sign in with Google accounts all need separate decisions. Forms can be rebuilt in Microsoft Forms; Sites may become a SharePoint page; automations might move to Power Automate. Make a list of every app staff sign into with their Google account, including accounting, CRM and booking systems, and plan how each will switch.

Phones and laptops need attention too. Remove the Google account from phones once mail has moved, add the Outlook app or the Microsoft account, and set up OneDrive on laptops. Shared calendars, room bookings and email signatures need recreating. A short instruction sheet for staff, with screenshots of the new sign-in, saves a lot of questions on the Monday morning.

Planning the timeline

For an office of ten to thirty people, a typical move runs over two to four weeks: setup and testing in the first week, bulk copying in the background, cutover over a weekend and a week of follow-up. Most of the risk sits in DNS, sharing and the forgotten apps rather than in the mail copy itself. Office IT quotes migrations like this in writing before any work starts.

Keep communication simple and frequent. Tell staff the cutover date, what they need to do on Monday, who to ask for help and how long the old system stays available. A move that is well explained in advance usually feels uneventful to staff, which is exactly the outcome you want.