What Doesn't Survive a Google Workspace to Microsoft 365 Migration

Every Google Workspace to Microsoft 365 migration quote answers the question "how do we move the mail and files?" Almost none of them answer the question that actually causes the pain six weeks later: what arrives broken, and what never leaves at all. The honest answer is that even the best third-party tooling moves your content and leaves the connective tissue behind. This is the inventory we walk clients through before anything moves, workload by workload.

First, the tool question

Three options dominate this route:

• BitTitan MigrationWiz is the industry default and the one we reach for on bounded cutovers. Pure SaaS, no servers to stand up, licensed per user at roughly $10 to $20 depending on what moves, with delta passes that let you re-run a mailbox until cutover day and DeploymentPro to rebuild Outlook profiles automatically.
• CloudM Migrate comes from Google-heritage engineers and tends to go deeper on Drive fidelity. Worth a look when Drive is the center of gravity rather than mail.
• Microsoft's native Migration Manager is free and handles Gmail, Calendar, Contacts, and Drive. For a ten-person company with simple needs it is genuinely fine. You give up throughput control, granular filtering, and the delta-pass workflow, which is exactly what you miss when something goes sideways at 2 a.m. on cutover night.

Here is the part vendors will not put on a pricing page: the tools differ less than their marketing suggests. All of them move the same core content competently. The reason "which tool" matters less than people think is that the hard losses below are not tool limitations. They are platform differences, and no license fee makes them go away.

What survives cleanly

• Mail, with attachments and folder structure derived from your labels.
• Calendar events, including recurrences and attendee lists.
• Personal contacts.
• Drive files, including Google Docs, Sheets, and Slides converted to Word, Excel, and PowerPoint on the way through.
• Shared Drive content, mapped to SharePoint libraries or Teams, usually licensed per drive on top of the per-user fee.

If your environment is mail, calendars, contacts, and ordinary files, the move is a known route. The trouble lives in the next two lists.

What survives, but damaged

• Labels become folders, and the model does not fit. Gmail lets one message carry five labels; Outlook puts a message in one folder. Tools either duplicate the message into every matching folder or pick one. The Social, Promotions, and Updates category tabs do not come at all, and snoozed or scheduled messages arrive as ordinary mail with their snooze and schedule state stripped.
• Contact groups arrive unsorted. The group folders get created at the destination, and then the contacts land in the top-level folder anyway. Somebody re-sorts them by hand, or nobody does.
• Converted Sheets lose their cleverness. QUERY, IMPORTRANGE, and GOOGLEFINANCE have no Excel equivalent, and any script attached to a spreadsheet dies in conversion. A finance team that runs on clever Sheets needs each one tested, and the clever ones rebuilt.
• Sharing survives only inside the company. Internal permissions map reasonably well. External collaborators are dropped, and every "anyone with the link" share dies silently, which brings its own line item below.
• Calendars carry their plumbing problems with them. Conference room calendars usually do not migrate and get rebuilt as Microsoft room resources. Event descriptions can drop on the way through. And every recurring meeting still contains a Google Meet link that will keep working and keep taking people to Meet long after you have paid for Teams. Each standing meeting needs its link replaced by hand.
• Signatures and out-of-office messages stay behind. Plan for everyone to rebuild both on day one.

What never leaves

• Gmail filters. Years of carefully built rules stay in Gmail. Power users rebuild them as Outlook rules by hand, and the people with 80 filters are always your most vocal employees.
• Anything built on Apps Script, Forms, Sites, or AppSheet. There is no migration path for any of these. The approval flow someone automated in 2021, the customer intake form, the intranet on Google Sites: these are rebuild projects in Power Automate, Microsoft Forms, and SharePoint, and they belong on the project plan as named line items with owners.
• Drive version history, and usually comments. Tools migrate the latest version of each file. Years of revision history stay behind, and comment threads range from partially preserved to gone depending on the tool. Plan as if both are gone, and export anything contractually important first.
• Every shared link in existence. Each Drive URL pasted into chats, wikis, bookmarks, and customer emails dies with no redirect. This is the single most common post-migration complaint, and the fix is communication before cutover, because there is no fix after.
• Google Chat and Spaces history. A handful of niche tools claim partial Chat-to-Teams moves; in practice, plan to archive the history for reference and start Teams clean. Meet recordings are ordinary files in Drive, so those do move.
• Google Groups as living things. The addresses can be recreated as distribution lists or shared mailboxes, but a collaborative inbox's conversation history and assignment state have no clean destination, and any Drive permission granted to a Group has to be re-modeled.
• Google Vault holdings. Data under legal hold has to be exported and preserved with chain of custody intact before anything is decommissioned, and the holds re-established in Microsoft Purview. If your company has ever been near litigation, this is a workstream of its own.
• Files owned by personal Gmail accounts. The founder's early documents shared in from a personal @gmail.com are legally that person's account, and no tool can touch them without that account's consent. Find them early; they are always the important files.

The migration plan this list implies

A clean Google exit is mostly an exercise in honesty before cutover. The rebuild items (filters, signatures, room calendars, Apps Script, Forms) go on the plan as named tasks with owners instead of being discovered as surprises. The communication pack tells everyone which links die and what to re-pin before they lose access, with a pilot group proving it a week ahead. And the freeze window keeps people from editing documents that have already moved. This is also why our migration intake asks about Apps Script, Vault, and Shared Drives before quoting a number: each one moves real work from "migration" to "rebuild," and a quote that ignores them is a quote you pay twice.

What it costs, with the tool priced honestly

A Google Workspace to Microsoft 365 move at standard scope (up to about 50 users, under 1 TB across Gmail and Drive, minimal Shared Drives, no SSO dependencies, nothing built on Apps Script, no Vault holds) is $3,500 fixed for the engagement, plus the migration tool licensing billed at cost, typically $10 to $20 per user. Bigger or messier scopes get a fixed quote after a scoped plan instead of a guess. If you are still weighing whether to move at all, start with our Microsoft 365 vs Google Workspace comparison, or request a scoping session and get a fixed number within one business day.