Microsoft 365 to Google Workspace: the complete playbook

This is the end-to-end guide for leaving Microsoft 365 for Google Workspace with MigrateX — an acquired Microsoft shop joining a Google-first company, a consolidation onto one suite, or a deliberate rebuild in Workspace. Between platforms nothing is "copied"; it is translated. This page says exactly what becomes what, what is written down instead, the order to work in, and how the domain moves from Microsoft to Google.

1 · Plan the move

Cross-platform moves carry one extra decision: what you are willing to lose in translation. Everything below the line in section 18 has no equivalent in Google; decide up front whether any of it matters enough to handle by hand.

Copy in waves, cut over once — and plan a day of hand-holding after cutover: people are changing app, not just tenant.

2 · What becomes what

Listed, not converted: Outlook rules and signatures, Teams tabs and apps, private channels, OneNote, Planner, sharing links. See section 18.

3 · Prepare both sides

In Google Workspace (target)

• Create the accounts with the same username as the Microsoft alias (aisha.rahman@) so auto-match pairs them.
• Assign Workspace licenses; Gmail and Drive turned on for the OU.
• A verified fallback domain (the Workspace's primary) that accounts hold until cutover. Google will not verify a domain still registered in Microsoft 365.
• A super administrator to authorise domain-wide delegation.

In Microsoft 365 (source)

• A Global Administrator for consent; the Exchange Administrator role for the MigrateX app if shared mailboxes and groups are in scope.
• Turn off concealed names in usage reports so sizes are readable.
• Decide what stays behind (leavers, archived sites).

In MigrateX

• Route Microsoft 365 → Google Workspace; scope: Mailboxes → Gmail, Shared mailboxes & aliases → Groups & aliases, OneDrive → Google Drive, Teams → Shared drives & Chat.
• Licenses: one per person, half per shared mailbox; Groups, shared drives, Chat and passes are free.

4 · Connect

1. Connect the Microsoft 365 sourceAdmin consent as the Global Administrator. Detail: Connect a Microsoft 365 tenant.
2. Connect the Google Workspace targetDomain-wide delegation with the scopes MigrateX shows, then a super administrator address and Verify. Detail: Connect a Google Workspace tenant.

5 · Assess

Findings specific to this route:

6 · Match users

Auto-match pairs by alias, then email alias, then unique display name; pair the rest by hand or CSV; exclude leavers. Detail: Matching users.

7 · Pilot

Pick people whose mailboxes exercise the conversion: deep folder trees, many categories and flags, a heavy calendar with recurring meetings, lots of shared OneDrive files. After the pass, sign in to Gmail as one of them and check:

• Nested labels match the folder tree; a few old messages carry the original dates; unread and flagged became unread and starred.
• A recurring meeting: recurrence and reminders intact, nobody re-invited.
• Drive: an Office file opens; sharing shows the same people with the same roles.

8 · Mail → Gmail

Each message is exported from Microsoft as MIME and imported into Gmail with its original date, read state and labels derived from its folder path. Categories become labels; flagged becomes starred; importance is kept. Deleted Items and Junk are skipped on purpose. Delta passes use Graph delta links on the Microsoft side, so a second pass carries only new and changed messages.

Doesn't convert: mailbox rules and signatures (recreate in Gmail settings — the notes list which users had them), Outlook client-only settings, messages over Gmail's size limit (listed by name).

9 · Calendar & contacts

• Events are converted field by field — title, body, times, time zone (Windows → IANA), reminders, free/busy, recurrence (Graph pattern → RRULE, with exceptions) — and imported, so attendees are not re-invited. Exchange-only recurrence shapes are approximated to the nearest RRULE and flagged in the report.
• Contacts become People contacts; contact folders become contact labels.
• Room and equipment mailboxes become Calendar resources where the API allows; otherwise listed.

10 · OneDrive → Drive

Files stream from OneDrive into Drive through memory; dates are kept; Office files stay Office files (Google opens them, and people can convert to Docs when they choose). Sharing is re-granted to the matched Google accounts with the same role. Sharing links and external people are listed as notes. OneNote notebooks are listed, not copied.

11 · Shared mailboxes & groups → Groups

On Groups & aliases, each shared mailbox becomes a Google Group with the same address, its Full Access people as members, its Send As people as managers, and its contents delivered into the Group's collaborative inbox where that is enabled. Distribution lists and Microsoft 365 Groups become Google Groups with their members. Aliases carry over; the ones on the moving domain are applied at cutover.

12 · SharePoint → shared drives

On Shared drives & Chat, each site's document libraries become a shared drive named after the site; Owners, Members and Visitors become managers, contributors and viewers. Lists, pages, web parts and workflows have no Google equivalent and are listed by name.

13 · Teams → Chat spaces

A team becomes one Chat space created in import mode; channel history is imported with the original authors and timestamps (channels merge into the space, each message prefixed with its channel name); team files land in a shared drive. The space stays staged, kept current by delta passes, until you make it available on cutover evening. Private channels, tabs, apps, reactions and 1:1 chats are listed.

14 · Waves & delta passes

Migrate by department while both suites stay live; run Run delta pass nightly. Microsoft's throttling on the way out and Google's quotas on the way in are both honoured across every worker; failures are retried up to five times.

15 · Verify

Migration → Verify everyone lists every folder, calendar and drive on the Microsoft side and checks each item against the Gmail label, Google calendar or Drive it became. Missing items are shown by name; Copy missing items queues them.

16 · Cutover evening

1. Freeze changesAsk people to stop creating content in Microsoft 365 for the evening.
2. Forward mail from Microsoft 365Each migrated mailbox forwards to its Gmail twin.
3. Final delta pass, then verifyCopy anything missing.
4. Make staged Chat spaces availableThey leave import mode and get their members.
5. Release the domain from Microsoft 365MigrateX moves every Microsoft user, group and shared mailbox to the tenant's fallback domain, then removes contoso.com.
6. Add and verify the domain in WorkspaceAdd the TXT record MigrateX shows; press Check.
7. Claim the addressesPrimary addresses and aliases on contoso.com are applied to the Google accounts and Groups.
8. Point DNS at GoogleGoogle's MX records, SPF include:_spf.google.com, DKIM from the Workspace Admin console, and remove Autodiscover. The wizard checks MX.
9. Send the notice, sign offThe notice for this route tells people how to set up Gmail on their phone and desktop. Print the report.

17 · The day after

• People are in a new app. Have a one-page "where things are now" ready: folders are labels, categories are labels, flagged is starred, Teams is Chat.
• Phones: add the Google account; remove the Microsoft one.
• Recreate Gmail filters and signatures for the people the notes list.
• External people need new sharing links from Drive.
• Keep the Microsoft tenant and forwarding for a month; run a delta and verify if anyone reports something missing.

18 · Limits and what is listed

Checklist