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Defined implementation

Plan your Microsoft 365 tenant merger around the deal timeline.

The agreed users, mail and files land in the receiving tenant. Sign-in and mail work on the new path, and every user is checked across both sides.

Plan the Tenant Move Review scope & terms

Price fixed after a short scope call. Price drivers and project calendar ↓

Illustrative sample · constructed example

Follow one person across both tenants.

Illustrative merger · project coordinator

Source tenant

The coordinator has a mailbox, OneDrive and project Team access.

Shared dependencies

Domain release, identity matching and coexistence have separate gates.

Target tenant

The same person tests each agreed workload in its destination.

Selected check

Is the domain transition agreed on both sides?

Evidence
Target account exists; domain release and sign-in timing are not approved.
Decision
Hold the affected wave
Next action
Both tenant owners agree the transition and user communication.

Illustrative sample. Workloads have different migration paths; a mailbox result is not a Teams or OneDrive result.

Open the complete illustrative document to inspect its fields and print a copy.

Open the sample document ↗

Tenant to Tenant Migration

The work starts here.

A sale, a purchase or a company split means one Microsoft 365 tenant has to move into another. The date is usually agreed before IT is asked.

Scope considerations

  • Clashes found before the first user moves
  • Checked user by user before sign-off
  • You own staff support on both sides

What AZ changes or delivers

  1. 01

    Everything in scope is counted on both sides before anything moves, and every user gets a named destination.

  2. 02

    The clashes are found first: shared domains, duplicate accounts, and security rules that differ between the two tenants.

  3. 03

    How much the two sides can see of each other during the move is decided and set up in advance, rather than discovered on the first morning.

  4. 04

    The move runs in dated groups, and each group is checked before the next one starts.

  5. 05

    The receiving tenant is checked against the source user by user, and every gap is closed or given an owner.

Acceptance

Checks before handover

  • Every user on the agreed list can sign in on the receiving tenant

  • Mail and files for those users have arrived and are tested

  • Every user is counted across both tenants, and anything deliberately left behind is written down with an owner and a date

Scope, price and project calendar

Engagement price

Price fixed after a short scope call.

The price is agreed in writing before any work starts and before anyone is given access. The call itself costs nothing. What moves the number:

What determines the scope

  • How many users are moving
  • Which parts of Microsoft 365 are in scope: mail, files, Teams, devices
  • Whether the two tenants have to work side by side during the move, and for how long
  • Whether devices have to be re-enrolled on the receiving side
  • How many domains move, and whether any are shared between the two businesses

Delivery calendar

The calendar is set once the data, the dependencies and the cutover requirements have been checked, then fixed in writing before the move begins.

How engagements work

Scope & responsibilities

Responsibilities and exclusions

Review the exclusions, required client participation, change controls and operational handover for this engagement.

Exclusions
  • Licenses needed to run the move, on either side
  • Application rebuilds or integrations on the receiving side
  • HR, payroll or finance system moves
  • Help desk and staff support
Client responsibilities
  • Confirm the list of users, domains and data that moves
  • Approve the switch window and the period the two sides run side by side
  • Give administrator access to both tenants
  • Tell staff on both sides what is happening and support them through it
Change and rollback method
  • Users move in dated groups, and a group is not started until the one before it checks out.
  • The conditions that stop the move are agreed before the first user moves, and they name conditions rather than intentions.
  • The domain move is scheduled as its own step, with its timers shortened in advance, because it takes sign-in and mail for everyone on it at the same moment.
Operational record and handover
  • The counted list of users, mail and files that moved
  • The list of clashes found and how each was settled
  • The dated schedule, as it actually ran
  • The agreed conditions for stopping
  • The check sheet proving source and destination match

Access, acceptance and support arrangements ↗

Discuss this engagement

Discuss Tenant to Tenant Migration

Describe the problem, systems and deadline. We will review the fit and the scope questions before preparing a written proposal.

Plan the Tenant Move