Whether your organization is switching platforms or you are moving on your own, you can transfer email, calendars, contacts, and files between Google Workspace and Microsoft 365 without losing data. The process works in both directions.

The best approach: run both in parallel during the transition. Set up the new platform, migrate your data, then gradually shift your daily work over a week or two before decommissioning the old one.

Google to Microsoft

Email

Option 1: IMAP sync (simplest for individuals)

1. Open Outlook (desktop app or new Outlook)
2. Go to File > Add Account (or Settings > Accounts > Add Account in new Outlook)
3. Enter your Gmail address and connect with your Google credentials
4. Outlook pulls in all your Gmail messages via IMAP
5. Drag and drop (or move) emails from your Gmail folders to your Outlook folders
6. Once everything is moved, remove the Gmail account from Outlook

Option 2: Google Takeout (export and import)

1. Go to takeout.google.com
2. Deselect everything, then select only Mail
3. Choose MBOX format and download the export
4. Import the MBOX file into Outlook using a tool like Aid4Mail or Thunderbird (as an intermediary)

Gmail labels do not map neatly to Outlook folders. Gmail allows one message to have multiple labels, but Outlook uses a strict folder hierarchy. Messages with multiple labels may end up duplicated across folders. Clean up labels before migrating if possible.

Calendar

1. Open Google Calendar
2. Click the three-dot menu next to the calendar you want to export
3. Select Settings and sharing
4. Scroll down and click Export calendar (downloads an .ics file)
5. Open Outlook Calendar or the Outlook desktop app
6. Go to Add calendar > Upload from file (web) or File > Open & Export > Import/Export (desktop)
7. Select the .ics file and import it

Repeat for each calendar. Shared calendars with other Google users will not carry over — the calendar owner needs to re-share or the other users need to subscribe to the new calendar.

Contacts

1. Open Google Contacts
2. Click Export in the left sidebar
3. Choose Outlook CSV format and download
4. Open Outlook People or the Outlook desktop app
5. Click Manage contacts > Import contacts (web) or File > Open & Export > Import/Export (desktop)
6. Select the CSV file and map the fields

Files (Google Drive to OneDrive)

For individual accounts:

1. Open Google Drive
2. Select all files and folders you want to move
3. Click Download — Google Docs, Sheets, and Slides automatically convert to .docx, .xlsx, and .pptx
4. Upload the downloaded files to OneDrive

For organization accounts:

Your IT admin can use Microsoft's Migration Manager (in the SharePoint admin center) to bulk-migrate Google Drive content to OneDrive or SharePoint. This preserves folder structure and permissions.

Google Docs, Sheets, and Slides convert to their Microsoft equivalents, but complex formatting (especially in Sheets with Google-specific functions) may not survive perfectly. Review important documents after migration.

Microsoft to Google

Email

Option 1: IMAP sync (simplest)

1. Open Gmail
2. Go to Settings (gear icon) > See all settings > Accounts and Import
3. Under Check mail from other accounts, click Add a mail account
4. Enter your Outlook email address and connect via IMAP
5. Gmail pulls in all messages. Once imported, remove the linked account

Option 2: Google Workspace migration (organization accounts)

Your IT admin can use the Google Workspace Migration for Microsoft Exchange (GWME) tool to bulk-migrate mailboxes from Exchange or Microsoft 365 to Google Workspace.

Calendar

1. Open Outlook Calendar (web or desktop)
2. Go to Settings > Calendar > Shared calendars (web) or select the calendar and use File > Save Calendar
3. Export as .ics file
4. Open Google Calendar
5. Click the gear icon > Settings > Import & Export > Import
6. Select the .ics file and choose which calendar to add events to

Contacts

1. Open Outlook People
2. Click Manage contacts > Export contacts
3. Download the CSV file
4. Open Google Contacts
5. Click Import in the left sidebar
6. Upload the CSV file

Files (OneDrive to Google Drive)

1. Open OneDrive
2. Select files and folders, then click Download
3. Upload to Google Drive
4. Word, Excel, and PowerPoint files can be opened directly in Google Docs, Sheets, and Slides — or converted using File > Save as Google Docs/Sheets/Slides

Things to watch out for

• Shared links break. Any Google Docs links you have shared with colleagues will stop working if you delete the originals. Keep the old account active (read-only) until everyone has updated their links.
• Google-specific formulas. Google Sheets functions like IMPORTRANGE, GOOGLEFINANCE, and QUERY have no direct Excel equivalent. Review spreadsheets that use these.
• Calendar invite replies. If you migrated a calendar event, replies from attendees go to whichever platform originally created the invite. For ongoing meetings, create new invites from the new platform.
• Storage differences. Google Workspace and Microsoft 365 have different storage quotas. Check your plan limits before migrating large Drive or OneDrive libraries.
• Two-factor authentication. You may need to generate an app password or grant OAuth access when connecting accounts via IMAP. Check your security settings if the connection fails.
• Email forwarding during transition. Set up forwarding from the old account to the new one so you do not miss messages during the switch. In Gmail: Settings > Forwarding > Add a forwarding address. In Outlook: Settings > Mail > Forwarding.

Running both in parallel

The cleanest migration strategy is to run both platforms for a week or two:

1. Set up the new platform and migrate data
2. Set up email forwarding from old to new
3. Update your email signature to mention the new address
4. Start sending from the new account
5. Once confident nothing is missing, stop checking the old one
6. Keep the old account active for a month in case stragglers still email the old address

short

Google to Microsoft: Export Gmail via IMAP or Takeout, export calendars as .ics, export contacts as CSV, download Drive files (auto-converts to Office formats), upload everything to Outlook/OneDrive. Microsoft to Google: Add Outlook to Gmail via IMAP, export calendar as .ics and import to Google Calendar, export contacts as CSV and import to Google Contacts, download OneDrive files and upload to Drive. Key tip: Run both in parallel during transition and set up email forwarding.