Use the EAC to move mailboxes
Using the Exchange Admin Center (EAC), you can move mailboxes from an on-premises organization to an Exchange Online organization, and from an Exchange Online organization to an on-premises organization.
Move on-premises mailboxes to Exchange Online organization
To move on-premises mailboxes to Exchange Online organizations, perform the following steps:
In the on-premises EAC, go to Home > Migration.
Select Add migration batch.
On the Add migration batch page:
- In the Give migration batch a unique name text box, enter a name for the migration batch.
- From the Select the mailbox migration path drop-down list, select Migration to Exchange Online.
- Select Next.
From the Select the migration type drop-down list, select Remote move migration, and then select Next.
On the Prerequisites for remote migration page, select Next.
Note
If you've already created a migration endpoint, you'll receive an endpoint confirmation prompt for this step. If you've created two or more migration endpoints, you must choose an endpoint from the Select migration endpoint drop-down list.
From the Select migration endpoint drop-down list, select a migration endpoint, and then select Next.
On the Add user mailboxes page:
Select Manually add users to migrate.
Note
The Manually add users to migrate option can be used to migrate a mailbox (or mailboxes) of a single user. If you want to migrate the mailboxes of users in bulk, use the Migrate from CSV file option. For more information on this option, see CSV files for Mailbox migration in Exchange Online.
In the Enter display names of mailboxes you want to migrate text box, enter the name or email address of the user whose mailboxes you want to migrate.
Select the mailboxes that you want to move to Exchange Online, and then Select Next.
Note
If shared mailbox accounts don't appear in the user selection list, you need to sync the shared mailbox on-premises AD accounts to Microsoft 365 or Office 365 by using cloud sync or Microsoft Entra Connect. The shared mailbox AD accounts appear as blocked accounts in the Microsoft 365 admin center and you can select them from the user list.
From the Target delivery domain drop-down list, select a domain, and then select Next.
On the Schedule batch migration page:
In the search box under After the batch is complete, a report will be sent to the following recipients. You must select at least one recipient to receive this report, enter a name or email address, and from the list displayed, select a user.
From the Start the migration batch by pane, select one of the following options:
- Manually start the batch later (by selecting it in the migration dashboard and then clicking Start): When you choose this option, the batch is saved with a Start button in the dashboard (the Migration batches page) for you to select whenever you want the batch migration to start.
- Automatically start the batch: When you choose this option, the batch migration starts immediately.
- Start the batch automatically after time: When you choose this option and set the date and time at which you want the batch migration to start, the batch migration automatically starts on the specified date and time.
From the End the migration batch by pane, select one of the following options:
- Manually completing the batch later (by clicking "Complete this migration batch" link on the right pane, after the link becomes active): When you choose this option, the batch that's to be migrated and that's displayed on the dashboard displays a Complete the migration button for you to select whenever you want.
- Automatically complete the migration batch: When you choose this option, the batch migration is completed automatically.
- Complete the batch automatically after time: When you choose this option and set the date and time at which you want the batch migration to complete, the batch migration automatically completes at the specified time.
Note
If you select Manually completing the batch later (by clicking "Complete this migration batch" link on the right pane, after the link becomes active) in step 9(c)(i), Exchange Online only synchronizes 95% of each mailbox in that batch. Exchange Online periodically synchronizes the batch to keep each mailbox at 95% synchronization until the batch is manually completed by selecting the Complete this migration batch, at which point the remaining 5% is migrated.
From the Select timezone drop-down list, select a timezone, and then select Save.
Note
The entries in the migration report are based on the UTC timezone by default. The admin can select another timezone (other than UTC) of choice from the Select timezone drop-down list. Then, the entries in the migration report will be based on the chosen timezone.
Select Done.
On the Migration batches page, select your migration batch, and then select Resume migration.
Select Confirm.
Close the page that displays the notification message Operation successful.
Check for your migration batch and verify whether its status is Starting.
If you encounter issues during the mailbox moves, or during the creation of a migration batch, see Troubleshoot migration issues in Exchange Server hybrid environment.
Move Exchange Online mailboxes to on-premises organization
You can use the remote move migration wizard in the EAC in Exchange Online to move existing cloud mailboxes to the on-premises Exchange organization:
In the Exchange Online EAC, go to Home > Migration.
Select Add migration batch.
On the Add migration batch page:
- In the Give migration batch a unique name text box, enter a name for the migration batch.
- From the Select the mailbox migration path drop-down list, select Migration from Exchange Online.
- Select Next.
From the Select migration endpoint drop-down list, select a migration endpoint, and then select Next.
On the Add user mailboxes page:
Select Manually add users to migrate.
In the Enter display names of mailboxes you want to migrate text box, enter the name or email address.
Select the mailboxes that you want to move to Exchange Online, and then Select Next.
Note
You must select a user mailbox, and not a shared mailbox. The user whose mailbox is being chosen for migration must be a mail-enabled user.
On the Move configuration page:
From the Target delivery domain drop-down list, select a domain.
From the Move options pane, select any one of the displayed options.
Under Target Database, in the Enter database name you'd like this mailbox to be moved to text box, enter the destination database to which you want to move the mailbox.
Note
The destination database is the one at the on-premises organization.
Select Next.
On the Schedule batch migration page:
Under After the batch is complete, a report will be sent to the following recipients. You must select at least one recipient to receive this report, in the search box, enter a name or email address, and then from the list displayed, select a user from the search results.
From the Start the migration batch by pane, select one of the following options:
- Manually start the batch later (by selecting it in the migration dashboard and then clicking Start): When you choose this option, the batch is saved with a Start button in the dashboard (the Migration batches page) for you to select whenever you want the batch migration to start.
- Automatically start the batch: When you choose this option, the batch migration starts immediately.
- Start the batch automatically after time: When you choose this option and set the date and time at which you want the batch migration to start, the batch migration automatically starts on the specified date and time.
From the End the migration batch by pane, select one of the following options:
Manually completing the batch later (by clicking "Complete this migration batch" link on the right pane, after the link becomes active): When you choose this option, the batch that's to be migrated and that's displayed on the dashboard displays a Complete the migration button for you to select whenever you want.
Automatically complete the migration batch: When you choose this option, the batch migration is completed automatically.
Complete the batch automatically after time: When you choose this option and set the date and time at which you want the batch migration to complete, the batch migration automatically completes at the specified date and time.
Note
If you select Manually completing the batch later (by clicking "Complete this migration batch" link on the right pane, after the link becomes active) in step *7(c)(i)**, Exchange Online only synchronizes 95% of each mailbox in that batch. Exchange Online periodically synchronizes the batch to keep each mailbox at 95% synchronization until the batch is manually completed by selecting Complete this migration batch, at which point the remaining 5% is migrated.
From the Select timezone drop-down list, select a timezone, and then select Save.
From the page that displays the message Batch creation successful, select Done.
Select your migration batch, and then select Resume migration.
Select Confirm.
Close the page that displays the notification message Operation successful.
Check for your migration batch and verify that its status is Starting.
Known issues
Inaccessibility to a network during mailbox onboarding: You may encounter a scenario wherein your connectivity to a network might have got terminated temporarily. This scenario can occur during or after you've onboarded an Exchange mailbox to the Exchange Online organization. To continue the process of "Exchange mailbox onboarding" or to access the onboarded Exchange mailboxes despite no network connectivity, perform the following task:
- Ensure that the Turn on offline access option is always enabled: Offline access in Outlook on the web (formerly called Outlook Web App) lets users access their mailboxes when they're not connected to a network. If you migrate Exchange mailboxes to Exchange Online, users have to reset the offline access setting in their browser to use Outlook on the web offline. For more information about offline access in Outlook on the web, the browsers that support it, and how to turn it on, see Using Outlook Web App offline.
Blockage in mailbox offboarding process: When you try to offboard an Exchange mailbox, you may receive a message that reads:
Error: MigrationPermanentException: Cannot find a recipient that has mailbox GUID <GUID>.For information on how to troubleshoot on seeing this error message, see the following article:
How do you know this worked?
When you move existing user mailboxes between the on-premises and Exchange Online organizations, the successful completion of the remote move wizard is your first indication that the "move mailboxes" process has completed as expected.
Because the mailbox move process takes several minutes to complete, you can also verify that the move is working correctly by opening the EAC and navigating through Office 365 > Recipients > Migration to display the move status for the mailboxes selected in the remote move wizard. The value of the Status is Syncing during the mailbox move, and it's Completed when the mailbox has successfully moved to either the on-premises or Exchange Online organization.
After the mailbox move has completed, you can check that the remote mailbox located on the on-premises or Exchange Online organization has been successfully moved by verifying the mailbox properties. To do this, go to Recipients > Mailboxes in the EAC for either the on-premises organization or Exchange Online organization. The user mailbox should show a Mailbox Type of Office 365 for Exchange Online mailboxes and User for on-premises mailboxes.
You can also run the following cmdlet in the Exchange Management Shell to verify the status of the migration batch:
Get-MigrationBatch -Identity <batch name>
Having problems? Ask for help in the Microsoft 365 and Office forums. To access the forums, you'll need to sign in using an account that's granted administrator access to your cloud-based service. Visit the forums at: Microsoft 365 and Office Forums.
To implement the next step of removing the completed migrated batches, see Remove completed migration batches.