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Guide · Tenant migration
Microsoft says there is no built-in way, and that is true. A team is four services in one, each with its own migration path or none. What actually arrives when tools migrate chat, and the decision that saves most of the cost.
By Alex Makey · 6 September 2026 · 8 min read · Verified against Microsoft documentation, September 2026
Microsoft’s own answer, when asked how to move Teams between tenants, is that there is no built-in method and a third-party tool is required. That is true and it is also incomplete. Here is what Teams actually consists of, what moves with which method, what does not move at all, and how to decide before anyone is disappointed.
Every team is a Microsoft 365 group underneath. The group has a mailbox in Exchange Online, a site in SharePoint, a membership list in Entra ID, and the Teams layer on top: channels, tabs, apps, and chat. Each of the four lives in a different place and migrates by a different mechanism — or does not migrate.
Tools that migrate channel conversations write them into the target using the Teams import API. What arrives is readable and searchable, but: messages appear under the migration account or with a note about the original author rather than as the person; reactions are usually lost; threads may flatten; @mentions become plain text; and the timestamps are preserved only if the tool supports it. Private chats between two people are harder still, because they are not a team — they belong to the users, and each pair has to be mapped.
This is not a criticism of the tools. It is what Microsoft’s API allows. Anyone promising a chat migration that looks identical to the source has not done one.
Do you need the chat history at all? Ask the teams that use Teams. Most channel conversations older than a few months are never read again. Files are different — people go back to files.
Three defensible answers, in order of cost:
Migrate files and structure, archive chat. Export channel conversations to HTML or PDF, store them in the migrated SharePoint site as a folder called Archive, and start the new tenant’s chat clean. Cheapest, fastest, and what we recommend for most consolidations. People can search the archive; they just cannot reply to it.
Migrate files, structure and channel conversations. Accept the fidelity limits above. Worth it when a team’s channel is the record — a project channel that functions as the project log.
Migrate everything including private chat. The most expensive option, with the most disappointment per pound. Justified rarely: regulated environments where chat is a compliance record, and even there an export to a compliance archive is usually the better answer.
1. Inventory. Every team, its group, owners, member count, channel count, site size, last activity. Teams with no activity in six months are archived, not migrated. On most estates that is a third of them.
2. Map users. Every member must exist in the target before the team is recreated. Mismatched or missing users are the commonest cause of a team arriving with the wrong membership.
3. Recreate the teams and channels in the target, empty, by tool or script. Check the names, the privacy setting and the owners before any content moves.
4. Migrate the SharePoint sites behind them with whichever SharePoint tool you are using for the rest of the estate. Files, folders, permissions. This is the part that carries the value.
5. Migrate or export conversations according to the decision above.
6. Recreate tabs, apps and connectors by hand, from the inventory. Planner boards, Forms and Whiteboards get their own decision each.
7. Set the source teams read-only, then archive them, once the target is validated. Do not delete them for at least the retention period.
Guests. External users in a team have to be re-invited in the target; their access does not move. Some will not accept the new invitation. Plan for it.
Private channels. They have their own SharePoint site, separate from the team’s. Tools that miss this migrate the team and lose the private channel’s files.
Shared channels. Cross-tenant by design. Sometimes the answer is not to migrate a team at all, but to connect it.
Teams Phone. Numbers are a separate port between tenants, taking days to weeks depending on the carrier. Start it first.
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Related questions
Partly, and only with third-party tools. Files and channel structure migrate well. Channel conversations migrate with fidelity limits set by Microsoft’s API. Private chat migrates imperfectly. Tabs, apps and connectors are recreated by hand.
Channel conversations can be migrated by tools but arrive with limits: authorship shown via a migration account, reactions lost, threads flattened, mentions as plain text. Private one-to-one chats are harder because they belong to users rather than teams. Many organisations export chat to an archive instead.
Because a team is four services combined: a Microsoft 365 group, an Exchange mailbox, a SharePoint site and the Teams layer. Microsoft provides migration mechanisms for the parts but not for the combination, and says so in its own guidance.
Their access does not move. Guests have to be re-invited to the team in the target tenant, and some will not accept the new invitation.
No. Teams with no activity in six months should be archived in the source, not migrated. On most estates that is around a third of them, and removing them from scope shortens the project.
Rather not do this yourself?
Describe the situation and you get back a sequence, an honest view of what will be slow, and a fixed price — usually within one business day. Or ask one question and get one answer.