- About This Article
- In a Word
- Key points requiring special attention in 2026
- Overall position within Google
- Why identity mapping is important
- Conceptual differences arising in migrations from Exchange
- Who is affected?
- Comparison with Microsoft migration tools
- Safe testing: Comparing counts before and after migration
- Security and Migration Quality
- Official Google Information
- What Should You Do Next?
- What Kind of Service Is It, Ultimately?
About This Article
This article was generated using an automated workflow powered by generative AI.
Google Workspace Migrate is an administrator-focused migration infrastructure for moving organizational data from Exchange, SharePoint/OneDrive, file shares, Box, and legacy Workspace to Google Workspace. Since the transition to the advanced data import tool is underway for some Microsoft 365 migration sources in 2026, old procedures should not be adopted as-is; instead, current official Google information must be verified.
Information Verification Date: 2026-09-19
In a Word
It is a tool for "moving from a legacy environment to Google Workspace." However, the migration project encompasses not just copying data, but also user ID mapping, sharing permissions, differences between folders and labels, delta migration, and cutover date planning.
| Perspective | Key Points | Items to Verify |
|---|---|---|
| Migration Source | Exchange, SharePoint/OneDrive, file shares, Box, etc. | Whether it is still supported by Migrate |
| Identity mapping | Mapping source users/groups to destination IDs | To whom permissions should be transferred |
| Mapping / template | Defining what to move and where | Unsupported features and conversion gaps |
| Main migration | Transferring core data | Count, errors, and missing items |
| Delta migration | Catching up on new and modified items immediately before production cutover | Differential data after final synchronization |
| Considerations for 2026 | Transition to new methods for certain Microsoft 365 components | Suitability of the advanced data import tool |
Key points requiring special attention in 2026
Official Google Help states:Google Workspace Migrate for SharePoint Online and OneDrive will no longer receive updates or bug fixes starting September 15, 2026, and the version for Exchange Online will become unavailable starting October 2026according to official guidance. When planning a new migration from Microsoft 365, first verify the transition to the advanced data import tool recommended by Google.
Therefore, simply knowing the product name Migrate is insufficient. Check the official matrix for each migration source to verify current support, migration destinations, transferable data types, and non-transferable settings.
Overall position within Google
Google Workspace Migrate is not a daily-use application, but rather anadministration tool for deployment and migration phases. Once migration is complete, daily operations shift to Gmail, Drive, Calendar, and others, and Migrate is not used continuously.
flowchart LR S[移行元 Exchange / Files / Box等] --> SCAN[調査・スキャン] ID[Identity mapping] --> MAP[Mapping / Template] SCAN --> MAP MAP --> MAIN[Main migration] MAIN --> CHECK[件数・エラー・権限確認] CHECK --> DELTA[Delta migration] DELTA --> CUT[Workspaceへ切替]
Why identity mapping is important
During migration, there is identity information such as who owns a file and with whom it is shared, alongside the files themselves. Identity mapping is the mechanism that associates source users, groups, and other entities with Google Workspace identities. Official Google documentation explains that it is used to connect sharing permissions, creation and modification metadata, and references including usernames to the migration destination.
For example, if former employees or legacy groups are mapped incorrectly, access permissions will not behave as expected even if the record counts match. Migration quality must be verified not only by file count, but also by owner, sharing permissions, timestamps, and folder-to-label conversions.
Conceptual differences arising in migrations from Exchange
The data model is not identical between the source and target; for example, Exchange folder hierarchies correspond to labels in Gmail. For shared mailboxes, calendars, and filters, verify the destination formats using official Google supported and unsupported lists along with monitoring points.
Who is affected?
General users and administrative staff
End users rarely operate the migration tool directly. The key is to perform acceptance testing after migration to verify where emails are located, how folders have been converted to labels, and whether shared files can be accessed.
IT administrators
Architect the source inventory, ID mapping tables, unsupported features, bandwidth, execution nodes, error retries, delta migrations, cutover, and rollback conditions. Especially for 2026, it is critical to check the product migration schedules for each source and avoid designing new configurations on deprecated pathways.
Developers and automation engineers
Rather than forcing automated operation of the migration engine itself, building helper tools that read and compare pre- and post-migration counts, CSVs, and permission lists is safer. If APIs are required, design the target service's Workspace API and authentication separately.
Comparison with Microsoft migration tools
| Perspective | Google Workspace Migrate | Microsoft 365 migration tools |
|---|---|---|
| Direction | Other environments to Google Workspace | Primarily other environments to Microsoft 365 |
| Identity | Mapped to Google Workspace identities | Mapping with Entra ID and M365 identities |
| Conversion | Convert to Google models such as Gmail labels | Convert to Microsoft models such as Exchange and SharePoint |
| Switch | Follow up using Main + Delta | Design phased migration and delta synchronization by methodology |
| Note | Method changes in some M365 migration sources in 2026 | Tools differ for each target workload |
For those with Microsoft experience, rather than grouping them together as a 'Google version of Migration Manager',it is safer to understand it as selecting Google's currently recommended path for each migration source.Safe testing: Comparing item counts before and after migration
Safe testing: Comparing counts before and after migration
You can compare item counts using dummy CSVs without making destructive changes to the Migrate core.
$before = Import-Csv ./before.csv
$after = Import-Csv ./after.csv
[pscustomobject]@{
Before = $before.Count
After = $after.Count
Delta = $after.Count - $before.Count
}
What to check: Before / After / Delta.Success criteria: Three values are displayed and match the expected count.Significance of changing one place: after.csv Adding one dummy row increases Delta by one, allowing you to verify the delta detection logic. Do not include real email addresses or internal IDs in the samples.
Security and Migration Quality
Since identity mappings contain real IDs, do not place them in public GitHub repositories.
Keep administrative privileges for migration to the strict minimum.
Protect temporary files, logs, and CSVs under the assumption that personal information may remain in them.
Check TLS and connection requirements in the official documentation.
Verify not only the number of successful items through sampling, but also owners, sharing settings, timestamps, and label or folder conversions.
Immediately before the cutover, verify the final delta after running a delta migration.
Official Google Information
What Should You Do Next?
First, categorize the source environment into Exchange Online, SharePoint Online/OneDrive, on-premises Exchange, file shares, Box, etc. Next, check the migration paths recommended by Google as of September 2026 for that source, run a complete cycle of mapping, conversion, delta migration, and acceptance testing with about 10 to 50 dummy or test items, and then proceed to the production plan.
What Kind of Service Is It, Ultimately?
Google Workspace Migrate is a migration infrastructure for moving organizational data to Google Workspace, but in 2026, transitions to successor methods are progressing depending on the migration source.
Rather than a simple data copy, treat IDs, permissions, data model conversions, deltas, and acceptance verification as a single migration project, and it is important to first check the current official recommended paths from Google.
