Overview
This article explains the supported and recommended methods for exporting email from Google Gmail and importing it into Microsoft 365. The correct method depends on whether you are migrating a single mailbox or an entire organization, and whether administrative access to Google Workspace is available.
Option 1 - Microsoft 365 Google Workspace Migration (Recommended)
This is the preferred method for full mailbox or tenant-wide migrations.
Use this method if:
- You are migrating one or more full mailboxes
- You want folders and labels preserved
- You have admin access to both Google Workspace and Microsoft 365
What is migrated:
- Email (Inbox, Sent, Drafts, folders)
- Gmail labels converted to folders
- Read and unread status
- Timestamps and attachments
Requirements:
- Google Workspace Admin access
- Microsoft 365 Global Administrator access
- Gmail API enabled
Step 1 - Prepare Google Workspace
1. Log in to the Google Admin Console
2. Enable the Gmail API
3. Confirm IMAP access is enabled for users
4. Create or authorize a service account or OAuth access for migration
Step 2 - Prepare Microsoft 365
1. Log in to the Microsoft 365 Admin Center
2. Navigate to Setup - Data migration
3. Select Google Workspace as the source
4. Create a new migration project
5. Authenticate Google Workspace access
6. Map Gmail users to Microsoft 365 mailboxes
Step 3 - Run the Migration
1. Perform a test migration
2. Start the full migration
3. Allow synchronization to complete
4. Perform a final sync before changing MX records
Option 2 - Google Takeout (MBOX) Export and Import
This method is commonly used when Google Workspace admin access is not available.
Step 1 - Export Gmail Using Google Takeout
1. Visit Google Takeout
2. Select Deselect all
3. Enable Mail
4. Choose export format MBOX
5. Download the archive when complete
Step 2 - Import MBOX into Microsoft 365
Microsoft 365 does not support direct MBOX imports. One of the following methods must be used.
Method A - Thunderbird (Free)
1. Install Thunderbird
2. Import the MBOX file
3. Add the Microsoft 365 mailbox using IMAP
4. Drag folders from Gmail into Microsoft 365
Method B - MBOX to PST Conversion
1. Convert MBOX to PST using a third-party tool
2. Upload the PST using the Microsoft 365 Import Service
3. Map the PST file to the correct mailbox
Option 3 - IMAP Migration (Basic Email Only)
This option is suitable for email-only migrations with limitations.
Steps
1. Enable IMAP in Gmail
2. Navigate to Setup - Data migration - IMAP in Microsoft 365
3. Enter Gmail IMAP server details
4. Provide user credentials or app passwords
5. Start the migration
Limitations
- Gmail labels may flatten
- Sent items may not migrate perfectly
- Calendars and contacts are not migrated
Best Practice Recommendation
If users will continue using Gmail during migration:
1. Run the initial migration
2. Allow mail to sync
3. Perform a final delta sync
4. Change MX records last
