Google Workspace to Microsoft 365 Migration Checklist

1. Take stock

• List every user, shared inbox, group and alias in Google Workspace.
• Measure mailbox and Drive sizes so you can estimate migration time.
• Note shared drives and who owns them.
• List anything else signing in with Google accounts: other apps, forms, scripts and integrations.

2. Prepare Microsoft 365

1. Buy the licences (Business Standard suits most small teams).
2. Add and verify your domain in the Microsoft 365 admin center, but don't change MX records yet.
3. Create users with the same email addresses they have in Google.
4. Create shared mailboxes for shared inboxes and Microsoft 365 groups for Google groups.
5. Plan where Drive content will go: personal files to OneDrive, shared drives to SharePoint sites or Teams.

3. Migrate email, calendars and contacts

Exchange Online has a built-in Google Workspace migration in the Exchange admin center. It copies mail, calendar and contacts in batches while people keep working in Gmail.

• Set up the Google Cloud project and service account the migration needs, following Microsoft's documented steps.
• Run a test batch with one or two mailboxes first.
• Migrate everyone else in batches, then let the sync keep them up to date until cutover.

4. Migrate Drive files

Migration Manager in the SharePoint admin center supports Google Drive as a source. Connect it, scan, review the report, then map each user's Drive to their OneDrive and each shared drive to its SharePoint destination.

5. Cut over

1. Pick a quiet time, such as Friday evening.
2. Update MX, SPF and autodiscover records to the values shown in the Microsoft 365 admin center.
3. Run a final sync so anything that arrived in Gmail is copied across.
4. Set up DKIM and DMARC for Microsoft 365 so your mail stays trusted.
5. Keep Google Workspace active for a few weeks as a safety net before cancelling.

6. Look after your people

Most migration problems are people problems. Send a short guide before cutover: how to sign in, set up Outlook and Teams on their phone, and where their files went. Be on hand for the first morning. A ten-minute walkthrough prevents a week of confusion.