Google Workspace to Microsoft 365 Migration in 2026: The Complete Checklist (What Migrates, What Doesn’t, and How to Avoid Downtime)

A Google Workspace to Microsoft 365 migration involves more than just moving emails. Emails, calendars, contacts, and files all need to be migrated, and there are variations in how each type of data operates within Microsoft 365. With a brief heads-up on what is transferred automatically, what may need setting up again, and what may cause problems will avoid delays, and this checklist outlines these together with the steps you will need to continue to offer your employees operational access.

What Actually Migrates

There are four main workload buckets you’ll likely be moving: mail, calendar, contacts, and files. Handled correctly, each one maps to a clear Microsoft equivalent.

Mail and mailbox structure

• Gmail messages, folders, and labels move into Exchange Online mailboxes
• Starred emails convert to Flagged items, since Exchange has no direct equivalent to Gmail stars
• Attachments transfer along with the parent message

Calendar and contacts

• Primary and secondary calendars, including recurring events and attendee responses, move to Outlook Calendar
• Contact entries and contact groups move to Outlook, though only entries with a valid email address populate correctly in a Contact List

Files and Drive content

• My Drive and Shared Drives move to OneDrive for Business or SharePoint Online
• Google Docs, Sheets, and Slides convert automatically to .docx, .xlsx, and .pptx
• Folder hierarchy and file version history carry over when the migration tool supports it

What Won’t Come Across Automatically

There are a few items that cannot simply be migrated across on the Microsoft 365 side and will need to be rebuilt because there’s no comparable product or the underlying structure doesn’t port over.

• Google Sites, since Microsoft has no direct equivalent; content is typically rebuilt in SharePoint
• Google Forms and Google Drawings, which need manual recreation or a rebuild in Microsoft Forms
• Google Chat history and Google Groups, which have no clean Microsoft counterpart
• Gmail filters and routing rules, which must be recreated as Outlook rules
• External sharing links, shortcuts to Drive files, and Google Meet links embedded in documents or invites, all of which break during the move
• Declined calendar events, room bookings, event colors, vacation responder configuration.

Knowing this list before the project starts will make many after the fact support tickets easier.

Pre-Migration Checklist

Before you migrate Google Workspace to Microsoft 365, there’s a small list of prerequisites, and completing them first can help prevent delays.

• Verify they have admin rights in Google Workspace Admin Console and Microsoft 365 admin center.
• Verify your ownership of the domain with Microsoft 365 using the TXT record Microsoft provides.
• Create user accounts in Microsoft 365 ahead of time, either manually, through CSV import, or via Microsoft Entra ID Connect
• Set up two subdomains for mail routing during coexistence, one pointed at Microsoft 365 and one at Google Workspace
• Build a CSV mapping file pairing each source Gmail address with its Microsoft 365 target
• Disable messaging records management and archival policies in Google Workspace before the batch starts; Microsoft’s migration tool flags items removed by those policies as missing
• Hold off on assigning Microsoft 365 licenses until the batch is ready to run

Running the Native Migration Path

Microsoft’s own tools handle the Google Workspace to Office 365 Migration without third-party software, split across two consoles depending on the workload.

For Email migration to Microsoft 365, the Exchange admin center runs an automated batch migration. Once the prerequisites above are in place, an admin creates a migration endpoint using a Google service account with domain-wide delegation, then builds a batch that pulls from the mapped CSV file.

For files, Migration Manager in the SharePoint admin center connects to the Google account, discovers Drive content, and maps it to OneDrive accounts, SharePoint sites, or Teams channels.

The setup of the service account, API scopes, and domain-wide delegation on the Google side, however, requires knowledge of Google Cloud Platform. Batches also run per workload rather than as one combined job, so mail, calendar, and Drive each need separate planning and separate monitoring. A five-person team can manage that without much trouble. A few hundred mailboxes with mixed Drive permissions, on the other hand, turn into a multi-week project with several people watching different dashboards.

A Simpler Route for Smaller or Selective Moves

Note: For organizations that would rather skip configuring a Google service account, managing API scopes, or running a separate batch for each workload, a dedicated desktop tool like the DRS Softech Google Workspace to Microsoft 365 Migration Tool is better suited to smaller-scale or selective migrations. It signs in directly with Google Workspace credentials instead of requiring backend API setup, which removes a step that trips up a lot of first-time admins.

Tools are managed from a single interface for Gmail, Contacts, Calendar, and Drive data and give some useful control:

• Move to a Microsoft 365 mailbox, public folder, or online archive
• Apply a date filter to move only messages within a chosen range
• Skip duplicate emails and skip folders such as Spam, Social, or Promotions
• Re-run a migration later with the skip previously migrated data option, without duplicating what already moved
• Map multiple Google Workspace accounts to their Microsoft 365 counterparts in one batch

It’s built for per-mailbox and selective migrations rather than large Shared Drive structures with layered permissions, so organizations moving thousands of files with nested sharing will still rely on SharePoint Migration Manager for that portion of the job.

Minimizing Downtime during Cutover

• Run a test batch with a handful of test mailboxes before migrating the full domain.
• During coexistence, both subdomains and Mail Exchange records stay active. So mail properly flows in both directions.
• Schedule the DNS cutover to Microsoft 365 outside business hours
• Re-run delta syncs close to cutover to support Email migration to Microsoft 365 and catch mail and calendar changes made after the first batch finished.
• Migrate in stages by department or location instead of moving the whole domain in one batch, particularly past a few hundred mailboxes.
• Communicate the Outlook rule and filter rebuild list to end users ahead of time, since those don’t move automatically.

Native Tools vs. a DRS Softech Tool

Note: If you need to export Google Workspace to PST. click it.

Conclusion

A migration of this size depends on careful preparation, not chance. Knowing what transfers directly, what needs to be rebuilt, and how to plan the cutover can help reduce downtime. Native migration tools can be suitable for large environments with complex permissions, while smaller organizations or selective, mailbox-level migrations may consider tools such as DRS Softech Google Workspace to Microsoft 365 Migration. It provides a single interface for migration tasks along with options for filtering and batch-level control.

Frequently Asked Questions