Tenant-to-tenant migrationBeta
Know what breaks before the cutover.
Merging, splitting or rebranding a Microsoft 365 tenant? Before anything moves, GraphPaaS reads the source tenant and lists what Microsoft's tools will refuse, what you'll rebuild by hand, which devices need a wipe, and which licences the source keeps paying for after the move.
- BlockerOneDrive over Microsoft's move limit1.2 M items
- BlockerApostrophe in the UPN….o'hara@…
- RiskMailbox at 90% of its quota or more95%
Microsoft's own limits
What moves, and what stays behind
Microsoft's cross-tenant tools move content, not tenants. The checks below come straight from their documentation.
Mail, calendar, contacts, archive, server-side rules, room mailboxes.
Blocked by any hold. Fails over the target quota. Leaves behind public folders, Send-as permissions, signatures, group mailboxes.
Files, versions, permissions and links, for people in the identity map.
Blocked over 5 TB or 1 million items (versions and folders count), by a hold, by an apostrophe in the URL.
Group, modern, classic and communication sites. EA only, licensed per 100 GB.
Same limits as OneDrive. Workflows, apps, Power Apps and flows are rebuilt. A team's site moves; the team does not.
Nothing. Users, groups and guests are created in the target first and matched.
A target user licensed before the match gets a mailbox, and the move then fails.
Nothing.
Conditional Access, Intune, app registrations, Teams, Planner, mail flow: rebuilt by hand. Devices enrol again.
The readiness check
Every name, not a score
Each check lists the people, sites and policies it found, so the report is the work list. A check whose data we don't have says “unknown”, never “ready”.
- OneDrive or site over 1 million items or 5 TB
- Apostrophe in a UPN that becomes a OneDrive URL
- With a target tenant picked: a target account that already has a mailbox, a OneDrive or an Exchange licence
- OneDrive or site past 800,000 items (our count leaves out versions, so it reads low)
- Mailbox at 90% of its quota or more
- Mailbox with an archive: submit it two weeks early
- External forwarding rules that move with the mailbox
- With a target: seats short per licence, Conditional Access that wants a compliant device, group names already taken
- Teams, Microsoft 365 groups and their owners
- Guests to re-invite
- Conditional Access policies and authentication methods
- Intune enrolment configurations, policies and apps
- App registrations and admin-consented enterprise apps
Only people who move are checked. A disabled or dormant account lands under “not to migrate” instead: archive it in the source rather than pay a migration licence for it.
Devices
One path per device
Intune has no tenant-to-tenant path: a device leaves the source and enrols in the target. How painful that is depends on how it was enrolled, so every managed device gets its path, its outcome and its primary user. The totals by outcome are the device side of your quote.
Licences
The source keeps paying
Under Microsoft's new commerce, seats can only be reduced in the first 7 days of a term. Move on the wrong date and the source pays for empty seats until each subscription renews.
- 01
Pick a cutover date
Every source subscription is set against it: seats × months still to pay, in euros when your price catalogue is loaded.
- 02
Count what to buy
Migration licences for the people who move, and SharePoint licences per 100 GB of sites.
- 03
Count what not to buy
Disabled and dormant accounts with data, listed by name.
Beta, and honest about it
What it doesn't do
Microsoft's own cross-tenant tools do that, run by your admin. GraphPaaS only reads the source tenant, with the same read-only permissions as the rest of the product.
Holds, public folders, Send-as rights, label encryption, Power Platform and Planner aren't in what we read. The report prints the read-only PowerShell commands that list them.
Microsoft licenses the move per migrated user and doesn't say whether a shared mailbox needs one, so we count them apart. A device whose join type Intune doesn't report falls back to its enrolment type. Plan with it; check it before you quote.