What is Office 365 migration?

Office 365 migration is the process of moving organizational data — mailboxes, public folders, archives, SharePoint, OneDrive, and Teams — into Microsoft 365, out to another platform, or between two tenants. EdbMails Office 365 Migration Software supports all of these scenarios.

How can I migrate to Office 365 using EdbMails?

The whole Office 365 migration process using the EdbMails Office 365 Migration Tool is one of the simplest there is – just connect to your source and target servers and let it do its work. Step 1: Download and install EdbMails. Step 2: Connect to the source using a global administrator account. Step 3: Choose which mailboxes and folders to migrate. Step 4: Connect to the destination server and map the mailboxes. Step 5: Begin the Office 365 migration process.

What are the reasons for migrating to Office 365?

Most teams move to Office 365 for some combination of these: Cost savings: Less spent on on-premise hardware, fewer painful upgrade cycles, and ongoing maintenance becomes someone else's problem. Scalability: Size your environment up or down as the business shifts. Accessibility: Mailboxes, documents, and apps reachable from anywhere, on whatever device the user happens to have. Collaboration: SharePoint, Teams, OneDrive, and Yammer working together for actual teamwork instead of email tag. Security: Built-in threat protection, data loss prevention, and encryption — without needing to bolt on third-party tools. Maintenance: Microsoft handles updates and patches, which frees IT staff for work that actually moves the business. Compliance: Features that help with HIPAA, GDPR, and the rest of the alphabet soup.

What types of Microsoft 365 migration does EdbMails support?

EdbMails covers all the standard Office 365 mailbox migration types. Cutover migration moves every source mailbox into the Office 365 tenant in a single pass — straightforward when the org is small enough to switch over at once. Staged migration breaks the work into phases, useful when you'd rather not move everyone at the same time. Hybrid migration ties on-premise Exchange and Office 365 together for organizations running both. IMAP migration is also on the menu — Gmail to Office 365 being one of the more common examples.

What are the best practices for Office 365 email migration?

The best practices guide for Office 365 mailbox migration covers all the key steps and recommendations to ensure a smooth and successful migration.

What are the migration challenges with Microsoft 365?

There are several common challenges with Office 365 mailbox migration including data integrity, downtime, user access continuity, and large mailbox handling. Detailed breakdown of these challenges is available in EdbMails' migration challenges guide.

Can I use EdbMails to migrate Microsoft 365 to On-Premise Exchange server?

Yes. EdbMails moves Office 365 mailbox data back to on-premise Exchange, with all server versions supported — Exchange 2010, 2013, 2016, and 2019. Step-by-step guidance for migrating from Office 365 to on-premise Exchange is available separately.

What are the steps to migrate Office 365 Public folder with EdbMails?

Public folder migration is straightforward with EdbMails — and there's no PowerShell scripting involved at any point. Step 1: Launch EdbMails and choose Office 365 migration. Step 2: Pick 'Connect to Public folder' as the migration operation. Step 3: Connect to the source Office 365 server and select the public folders. Step 4: Connect to the target Office 365 server and start the migration.

Can I migrate a Microsoft 365 Public folder to Shared mailbox with EdbMails?

Yes - Office 365 public folder to shared mailbox migration is one of the supported scenarios.

How to migrate a large Archive mailbox to Office 365 with EdbMails?

For migrating a large archive mailbox to Office 365: Step 1: Enable In-Place Archive in your Office 365 tenant. Step 2: Download and install EdbMails. Step 3: Connect to the source Office 365 server. Step 4: Pick the large archive mailbox you want to move. Step 5: Connect to the target Office 365 server. Step 6: Start the migration. Every piece of mailbox data — emails, contacts, calendars, tasks, attachments — comes across with full accuracy. No data loss, no corruption, nothing scrambled.

Which license do I need to buy to migrate Office 365 Mailboxes?

You'll need an Office 365 Migration license to move your mailboxes from Office 365.

Can I migrate only new emails using EdbMails without duplicates on the target server?

Yes. By default, the first run is a full migration. From the second run onward, incremental migration kicks in automatically, picking up only new or modified items — no duplicates land on the target. You can also filter by last migration date if you'd rather skip rescanning the whole mailbox each time.

Do I need to pay for Shared mailbox migration?

Yes — each shared mailbox uses up one license, same as a regular mailbox.

Is there a Free Trial version available to test Microsoft 365 migration features?

Yes — there's a Free Trial that opens up every Office 365 migration feature for testing. Up to 30 items per folder from every mailbox come across during the trial.

Is it possible to migrate specific data from source Office 365 to target Office 365?

Definitely. EdbMails handles selective Office 365 migration through filters that you can shape pretty granularly — message received date, sender address, recipients (CC and BCC included), subject line, attachment names, and read/unread status all work as filter criteria.

How do I choose the best Office 365 migration software?

Compare migration tools across capabilities like license type, concurrent mailbox migration, automatic throttling management, incremental migration, public folder licensing, and technical support. Tools that offer lifetime licenses, free upgrades, and 24/7 support typically deliver better long-term value than subscription-based options.

How does the licensing work?

The licensing model is per-mailbox: each migrated mailbox consumes one license, calculated against the source mailbox count. Nothing stops you from running multiple migration jobs in parallel across different machines, as long as you've got licenses left in the pool.

Do you have Office 365 Migration checklists?

Yes - Office 365 migration checklists are available to help you plan and execute your migration successfully.

How many licenses should I purchase for Public folder migration?

Public folder migration takes 20 mailbox licenses. Once those are allocated, you can migrate unlimited public folders from a domain — there's no per-folder cost beyond that.

Does EdbMails support migrating Shared mailboxes to Office 365?

Yes — shared mailbox migration to Office 365 tenants is fully supported. The full set of source items is covered: mailboxes, shared mailboxes, public folders, archive mailboxes, and more. EdbMails handles the shared-mailbox mapping automatically and brings across the contents — emails, attachments, contacts, calendars, tasks, and notes.

Is there any size limitation for Microsoft 365 mailbox migration?

There aren't any size limits on the EdbMails side. Microsoft does enforce its own restrictions, though — those are detailed in the EdbMails Knowledge Base article on Microsoft 365 mailbox size limitations.

Does EdbMails create the mailboxes automatically on the target O365 server?

Yes, EdbMails will automatically create the mailboxes for you on the target and allocate the licenses to be assigned.

Is it possible to map one source folder to the target folder of my choice on the server?

Yes, EdbMails allows customized folder mapping to route source folders to target folders of your choice.

How much time does it usually require to migrate Office 365 mailboxes?

The duration of Office 365 migration depends on a few moving parts. Detailed breakdown of Office 365 migration duration is available in EdbMails' tenant-to-tenant migration guide.

Does the software support all languages during migration?

Yes — EdbMails supports all languages during Office 365 migration.

Can I access the source and target mailbox during migration?

Yes — your mailbox data stays accessible the whole time the migration is running. No server downtime to plan around.

Can EdbMails remove deleted source items from the target Office 365 folders?

Yes — EdbMails can sync deletions from source to target. Tick the 'Remove deleted source items from target folders' option in the main migration window, then run a follow-up migration.

Can I migrate emails from Microsoft 365 to IMAP server using EdbMails?

Yes — Office 365 emails can move to any IMAP-enabled server. The supported list covers most of the popular ones: Outlook, Gmail, Zoho, Zimbra, IceWarp, cPanel, Plesk, GoDaddy, Rackspace, AWS WorkMail, Bluehost, and Dreamhost.

Does EdbMails support Office 365 to Hosted Exchange migration?

Yes — Office 365 to Hosted Exchange is supported. A common example is migrating from Office 365 to a Rackspace-hosted Exchange server.

Will I require a different license for Primary mailbox migration and Archive mailbox migration?

No, you only need one license if both the UPN (User Principal Name) are identical for the Primary and Archive mailboxes.

Does EdbMails manage mailbox mapping from source to target Microsoft 365 server automatically?

Yes, EdbMails automates the mailbox mapping between source and target tenants. For the case when there are hundreds or thousands of mailboxes to be migrated, manual mapping would be a terrible job and EdbMails saves a lot of time.

Does the software generate duplicates when running consecutive Microsoft 365 migrations?

No — incremental migration handles this. Subsequent runs only carry across new and modified items, which keep the target server clean of duplicates.

Does EdbMails handle mailbox mapping between source and target Microsoft 365 servers automatically?

EdbMails automates mailbox mapping between the source and target Tenants, which is useful for large-scale migrations, saving considerable time and effort compared to manual mapping.

Does EdbMails need scripting via PowerShell for Office 365 migration?

No. EdbMails Office 365 migration is an all-graphical-user-interface experience without need of using any PowerShell scripts, or any command-line instruments, or making any API calls. This is regardless of whether it is about migrating mailboxes across tenants, public folders or mailbox archives, hybrid configuration.

Does EdbMails support Office 365 to Office 365 migration between two different tenants?

Yes. Migrating data <a href="https://www.edbmails.com/pages/office-365-migration-guide.html">between any two different Office 365 (Microsoft 365) tenants</a> is exactly what EdbMails Office 365 Tenant to Tenant Migration Tool is built for. It's a common ask during company mergers, acquisitions, and corporate restructures, and the cross-tenant workflow is the same regardless of which scenario is driving the migration. For a quick overview of the process, see our <a href="https://www.edbmails.com/pages/office-365-to-office-365.html">Office 365 to Office 365 migration overview</a>.

What is Microsoft 365 cross-tenant migration?

Microsoft 365 cross-tenant migration is the process of migrating mailboxes and workloads, including SharePoint, OneDrive, and Teams, from one Microsoft 365 tenant to a separate, independent tenant. It differs from an in-tenant migration because the source and target exist as fully separate Microsoft 365 environments with their own domains and licensing. <a href="https://www.edbmails.com/pages/cross-tenant-office-365-migration.html">Click here to know the steps to perform Office 365 Cross Tenant Migration</a>.

How do I migrate from one Microsoft 365 tenant to another?

Connect EdbMails to the source Microsoft 365 tenant, select the mailboxes and workloads to migrate, connect to the target tenant, confirm the mailbox mapping, and start the migration. See the <a href="https://www.edbmails.com/pages/office-365-tenant-to-tenant-migration-step-by-step-guide.html">step-by-step migration guide</a> for the full walkthrough.

How much time does it usually take to migrate Office 365 tenants?

Migration time depends on data volume, mailbox count, available bandwidth, and Microsoft server response at the time of migration. EdbMails controls throughput through parallel mailbox migration, parallel item processing across multiple threads, automatic throttling management, and full restart/resume support if a job is interrupted. Parallel migration produces the largest speed gain, since migrating several mailboxes between tenants at the same time cuts total runtime compared to a sequential approach. A few Microsoft-imposed limits affect migration speed regardless of tool: individual items are capped at 25 MB by default, which <a href="https://www.edbmails.com/pages/office-365-migration-faq.html#sizelimit">can be increased to 150 MB</a>; throttling policies on both source and target tenants can affect transfer rate; the type and volume of data being migrated affects speed; and network setup at the migration machine affects throughput. For more detail, refer to <a href="https://learn.microsoft.com/en-us/Exchange/mailbox-migration/office-365-migration-best-practices">this Microsoft article</a>. To increase throughput, consider <a href="https://www.edbmails.com/pages/general-faqs.html#parallel-migration">increasing the number of parallel migrations</a> or <a href="https://www.edbmails.com/pages/disable-ews-throttling-in-exchange-online.html">increasing throttling policy limits in Exchange Online</a>.

Is a Free Trial available to test tenant to tenant migration features?

Yes. The <a href="https://www.edbmails.com/pages/download.html">Free Trial</a> lets you test tenant to tenant features before purchase, migrating every mailbox in scope with up to 30 items per folder transferred. That's enough to evaluate mapping behavior, incremental sync, filter settings, and reporting.

Does the software support all languages during migration between tenants?

Yes. <a href="https://www.edbmails.com/pages/office-365-migration-languages-supported.html">Language support</a> applies regardless of source or target tenant locale. Folder names, message body content, and special characters, including accented letters, CJK characters, and right-to-left scripts, are preserved on the target.

What kind of data does the EdbMails Tenant to Tenant migration tool migrate?

The tool covers <a href="https://www.edbmails.com/pages/migrate-emails-calendars-and-more.html">emails, contacts, calendars</a>, tasks, journals, and notes across primary mailboxes, shared mailboxes, public folders, and archive mailboxes.

Can shared mailboxes, archive mailboxes, and public folders be migrated between tenants?

Yes. <a href="https://www.edbmails.com/pages/migrate-shared-mailbox-to-office-365.html">Shared mailboxes</a>, <a href="https://www.edbmails.com/pages/office-365-archive-migration-to-office-365-guide.html">In-Place Archive mailboxes</a>, and <a href="https://www.edbmails.com/pages/office-365-public-folder-migration-to-office-365-guide.html">Public Folders</a> all migrate between Office 365 tenants with their data intact. Public folders carry over with subfolders, mail-enabled folders, items, and permission structure preserved; In-Place Archives keep historical email accessible on the destination; and shared mailboxes arrive with team-collaboration workflows functional on the target from day one.

Can SharePoint, OneDrive, and Teams be migrated between tenants?

Yes. <a href="https://www.edbmails.com/pages/sharepoint-migration-guide.html">SharePoint Online</a>, <a href="https://www.edbmails.com/pages/onedrive-migration-guide.html">OneDrive for Business</a>, and <a href="https://www.edbmails.com/pages/microsoft-team-migration-guide.html">Microsoft Teams</a> are each supported as separate workload migration modules alongside mailbox migration.

Which license do I need for a tenant to tenant migration?

For migrating mailboxes, shared mailboxes, public folders, and archive mailboxes, the Office 365 Migration license is required. Each fresh source email address consumes a license. Public folders consume 50 mailbox licenses, which lets you migrate unlimited public folders from the same domain. <a href="https://www.edbmails.com/pricing.html#office-migration">See Office 365 Migration pricing details</a>. For SharePoint, OneDrive, Teams, Channels, and 1:1 chats, the 'SharePoint + OneDrive + Teams' Migration license is required. The license count is based on the number of source sites for SharePoint and Teams, plus the number of OneDrive users whose data you want to migrate. Buying licenses in bulk saves you more, and any unused licenses stay available for future use. <a href="https://www.edbmails.com/pricing.html#sharepoint">See 'SharePoint + OneDrive + Teams' Migration pricing details</a>.

Does EdbMails automatically create mailboxes on the target?

Yes, you can choose to let EdbMails automatically create mailboxes on the target Office 365 tenant. <a href="https://www.edbmails.com/pages/automatically-create-and-license-office-365-user.html">Click here to know more about automatic mailbox creation</a>.

Does EdbMails automatically map mailboxes between tenants?

Yes. EdbMails matches source mailboxes to their target counterparts using user attributes. <a href="https://www.edbmails.com/pages/automatic-mailbox-mapping.html">Automatic mailbox mapping</a> is particularly useful on migrations involving several hundred or several thousand accounts.

Does the software generate duplicates on consecutive runs, and can migration be performed incrementally?

No duplicates. <a href="https://www.edbmails.com/pages/office-365-incremental-migration.html">Incremental (delta) migration</a> runs by default from the second migration onward, transferring only items that are new or changed since the last run. Items already on the target tenant stay in place across repeated runs, so consecutive migrations never create duplicates.

Can selective data be migrated from one tenant to another?

Yes. <a href="https://www.edbmails.com/pages/office-365-migration-filter-settings.html">Filtering</a> supports inclusion or exclusion by received date, sender, recipient, CC/BCC fields, subject line, attachment names, and read/unread status.

Are there size limitations for Office 365 tenant mailboxes during migration?

EdbMails does not impose a mailbox size cap for tenant to tenant migration. Microsoft sets platform-level limits that apply regardless of migration tool; refer to <a href="https://www.edbmails.com/kb/microsoft-365-mailbox-size-limitations.html">this Knowledge Base article</a> for current figures.

Is data safeguarded throughout the migration process?

Yes. Migration runs through Microsoft's APIs, with <a href="https://www.edbmails.com/pages/security.html">authentication handled by OAuth 2.0 and TLS encryption</a>. Credentials are not exposed during the process. Modern Authentication uses MSAL (Microsoft Authentication Library) and Microsoft Graph, the path Microsoft recommends for tools accessing a tenant.

Office 365 Tenant to Tenant Migration Tool

What is Office 365 tenant-to-tenant migration?

Office 365 tenant-to-tenant migration moves users' mailbox data and other supported Microsoft 365 workloads from one tenant to another. Organizations commonly perform it during mergers, acquisitions, divestitures, tenant consolidation, rebranding, or internal restructuring. The exact preparation and migration sequence depends on the workloads, identity and domain plan, licensing, and cutover requirements.

Migrate now

What to look for in an Office 365 tenant-to-tenant migration tool

A tenant migration tool should match the workloads and cutover model you actually need. Before choosing a product, confirm how it handles the areas below and verify any workload-specific limitations.

Workload scope

Confirm whether you need mailbox-only migration or separate support for OneDrive, SharePoint, Teams, public folders, archives, shared mailboxes, or other workloads.

Source-to-target mapping

Look for practical ways to map users and mailboxes at scale, including manual or CSV-based control where needed.

Repeat migration

Incremental or delta passes help move new or changed content after the initial migration and support staged cutover planning.

Filtering and batching

Large projects benefit from selective scope, batches, and controls that let administrators move the right users and data in manageable waves.

Authentication and security

Verify how the tool authenticates to Microsoft 365 and how credentials and migration data are handled.

Reporting and validation

Administrators need clear migration status, errors, item counts, and post-migration checks before final cutover.

Common Scenarios for Office 365
Tenant to Tenant Migration

Mergers and Acquisitions

When two companies become one, unifying their Office 365 environments is usually one of the first IT priorities, since shared calendars, Teams channels and document collaboration do not work across separate tenants. EdbMails moves the acquired organization's selected data into the primary tenant so teams can transition collaboration to the target environment according to the planned cutover.

Divestitures and Spin-offs

Carving out a business unit means separating a subset of users and their data into a new, independent Office 365 tenant without disrupting the parent organization. EdbMails copies the selected data to the new tenant while the source remains available, giving the spun-off entity access to migrated historical email and supported document data after cutover.

Rebranding or Restructuring

Domain changes, entity consolidations and corporate rebrands often require mailbox migration between Office 365 tenants, even within the same parent company. EdbMails supports tenant reconfiguration aligned with the business timeline.

Improved Tenant Structure

Tenant Consolidation

Organizations running multiple Office 365 tenants for historical reasons can consolidate into a single environment. EdbMails handles tenant consolidation with automatic mapping and incremental migration, supporting tighter management, security and compliance across a single environment.

Why Choose EdbMails for Office 365 Tenant to Tenant Migration?

Premier Tenant to Tenant Migration Solution

EdbMails automates key tenant migration tasks and reduces manual administrative effort throughout the project. Parallel mailbox migration lets multiple Office 365 mailboxes transfer between tenants at the same time, keeping migration windows short even with hundreds of users. Incremental (delta) sync picks up only items that are new or modified since the last run, so repeat migrations stay quick and duplicate-free on the target. Advanced filters give administrators control over which mailboxes, folders or content types transfer, so only the data the cutover needs makes the move.

Effortless Migration Process

EdbMails automates the tenant to tenant migration process from connection through mapping. The interface guides each step, while automatic mailbox creation and source-to-target mapping handle work that typically slows these projects down. Connecting to both source and target Office 365 tenants requires no scripting; CSV import remains available for administrators who prefer manual mapping control. Microsoft 365 service quotas, item limits, and throttling can still affect migration performance and item eligibility.

User Friendly Interface

The interface is designed so that any IT administrator, including one running a cross-tenant migration for the first time, can complete the process without getting stuck. Each step is clearly labeled, and the workflow surfaces the information administrators need at that stage rather than technical terminology that gets in the way. Comprehensive documentation and the support team are available if a question comes up along the way. The result is a migration experience that stays approachable rather than overwhelming.

Secure Data Migration

Security is a priority whenever sensitive corporate data moves between Office 365 tenants. The platform is ISO 27001:2013 certified and GDPR compliant. Data in transit is protected by SSL/TLS encryption, authentication runs through OAuth 2.0 with Modern Authentication, and Multi-Factor Authentication (MFA) is supported on both source and target tenants. With these safeguards in place, data stays protected throughout the cross-tenant move.

Know more...

Cost Effective Migration

EdbMails comes in at a lower cost than comparable cross-tenant migration tools, with a pricing model that stays simple. A license is consumed only when you add a fresh source mailbox, and once licensed you can re-run that mailbox as many times as you need at no extra cost. Unused licenses stay available for future migrations, with no domain or client restrictions and no expiry. Software upgrades are free, so the price you see is the price you keep.

Buy now

24 / 7 Free Technical support

Free round-the-clock technical support comes with every license, with no tiers, no paywalls, and no queue priority based on spend. The team is available via live chat, email, and phone, with remote sessions available whenever a tenant migration needs hands-on troubleshooting. Setup help and mid-migration questions are covered from the very first step onward, whenever you need them. Customer satisfaction remains the top priority.

Live chat support

Office 365 Tenant Migration Challenges & EdbMails Solutions

Tenant Migration Challenge	EdbMails Capability
Hundreds or thousands of mailboxes	Parallel migration
User mapping	Automatic mailbox mapping
Changes during migration	Incremental migration
Avoiding repeated processing	Incremental processing and migration history
Large mailboxes	Scalable mailbox migration
Microsoft throttling	Automatic throttling management
Selective migration	Advanced filters
Migration verification	Detailed migration reports
Target provisioning	Automatic mailbox creation where supported
Authentication	OAuth 2.0 / Modern Authentication
Business continuity	Source and target tenants remain operational during migration

Key Features and Capabilities of
EdbMails Office 365 Tenant to Tenant Migration Tool

Parallel Mailbox Migration

Parallel mailbox migration is where the time savings show up most on a tenant to tenant project. EdbMails transfers multiple Office 365 mailboxes between tenants at the same time, which compresses migration windows compared to sequential approaches. Know more

Automatic Mailbox Mapping

EdbMails pairs source and target mailboxes automatically using automatic mapping, removing the need to match names manually. This saves setup time on migrations involving more than a hundred mailboxes.

Incremental Migration

Incremental (delta) migration runs by default from the second migration onward. Only items that are new or changed since the last run transfer to the target, so re-runs stay fast and duplicates do not appear on the destination.

Migration with Reduced User Disruption

Users can continue working in source mailboxes during the data-migration phase; cutover requirements and any interruption depend on the domain and migration scenario. Review migration continuity considerations when planning the cutover.

Selective Data Migration

Selective data migration gives administrators control over what transfers between tenants. Filter by date range, sender, recipient, CC, BCC, attachments or read/unread status to migrate only the data the target tenant needs.

Enhanced Migration Reporting

Detailed migration reports cover the full tenant to tenant migration, including status per mailbox, folder-level breakdowns and item counts that can be verified against the source.

Automatic Creation of Target Mailboxes

EdbMails provides target mailbox creation options for supported Office 365 migration scenarios. Confirm the current licensing prerequisites and supported provisioning workflow before using this option.

Supported Mailbox Item Types

Supported mailbox item types include emails, calendars, contacts, tasks, notes and journals, along with supported attributes.

More Features

What Gets Migrated During Your
Microsoft 365 Tenant to Tenant Migration

Office 365 to Office 365 migration - Office 365 Tenant Migration

Mailbox Migration

EdbMails transfers supported user mailbox data, including emails, contacts, calendars and tasks, between Office 365 tenants.

Office 365 migration guide

Office 365 Groups

EdbMails provides Office 365 Groups migration for supported group data. Verify the specific group components and target prerequisites required for your migration before cutover.

Office 365 Groups migration

Public Folders

EdbMails migrates supported public folder content and folder hierarchy between Office 365 tenants. Confirm workload-specific permission requirements before the production move.

Office 365 public folder migration

Shared Mailboxes

EdbMails migrates supported shared mailbox data between Office 365 tenants. Validate target access and mailbox configuration as part of the post-migration checks.

Shared mailbox migration

IMAP Migration - Tenant to Tenant Migration Office 365

Resource Mailboxes

EdbMails migrates supported resource mailbox data between tenants. Verify booking and resource configuration requirements separately before cutover.

Resource mailbox migration guidance

Archive Mailboxes Migration

EdbMails migrates supported In-Place archive mailbox data between Office 365 tenants. Validate archive access and retention requirements on the target after migration.

Archive mailbox migration

SharePoint Migration

Use the EdbMails SharePoint migration module to move supported site collections, document libraries, lists and related data between Microsoft 365 tenants. Verify permission and configuration requirements for the SharePoint workload before migration.

SharePoint tenant migration

Microsoft Teams Migration

Use the EdbMails Microsoft Teams migration module to move supported Teams data between Microsoft 365 tenants. Review the supported Teams components and target requirements before the production migration.

Microsoft Teams migration

OneDrive Migration

Use the EdbMails OneDrive migration module to move supported user files, documents and folder structures between Microsoft 365 tenants. Validate target access and sharing requirements after migration.

OneDrive tenant migration

Microsoft Native Cross‑Tenant Migration vs EdbMails

Evaluation Area	Microsoft Native	EdbMails
Initial configuration	Organization Relationship, Migration Endpoint, Entra app registration, Azure Key Vault	Guided product workflow
PowerShell requirement	Required (Exchange Online PowerShell, MRS)	Minimizes manual scripting where the product handles configuration
Mailbox mapping	Manual (pre‑created MailUser objects with matching GUIDs)	Automatic mapping
Filtering	Not available at item or content level	Advanced filters
Incremental migration	Supported via MRS batch sync until cutover	Supported where applicable
Reporting	PowerShell only, no dashboard	Detailed migration reports
Support	Standard Microsoft 365 plan‑based support	24/7 Free Technical Support
SharePoint / OneDrive / Teams	Not covered by mailbox migration; partial coverage via Orchestrator (Public Preview)	Available through EdbMails workload migration modules

Accelerate Your Office 365 Tenant Migration with EdbMails

Tenant to tenant migration speed depends on hardware utilization, Microsoft 365 throttling behavior, network conditions, and the structure of the source and target tenants, including permissions, metadata and folder hierarchy complexity. EdbMails manages these factors automatically, using available hardware efficiently, handling throttling in the background, and adapting to the source and target tenant configuration. Learn more about how to speed up your Office 365 migration

Know more

Plan the tenant migration before you move data

Tenant-to-tenant migration is not only a data-copy task. Identity mapping, domain changes, workload dependencies, licensing, migration waves, and the cutover sequence can affect the project. Define these items before starting the production migration.

Inventory the users, mailboxes, archives, public folders, OneDrive, SharePoint, Teams, and other workloads in scope.
Decide how source users map to target users and whether UPNs or domains will change.
Identify same-domain moves early because domain transfer requires its own cutover sequence.
Plan migration batches, pilot users, repeat/incremental passes, and the final cutover window.
Confirm target licensing and workload-specific prerequisites before migration.
Define how the team will validate migrated data, mail flow, access, and user readiness after cutover.

For the detailed procedure, use the Office 365 tenant-to-tenant migration step-by-step guide. If the same domain must move between tenants, review Office 365 migration with the same domain before planning cutover.

How Office 365 tenant-to-tenant migration
works with EdbMails

High-level migration process

Prepare: Confirm the users, workloads, target accounts, licensing, domain plan, and migration batches before production migration.
Connect: Connect the source and target Microsoft 365 tenants using the supported EdbMails authentication method.
Select and map: Select the mailboxes or supported data in scope and map source objects to the required target destinations.
Migrate and re-run: Start the migration and use supported incremental/repeat passes to move new or changed mailbox items before cutover.
Validate and cut over: Review migration reports and target data, then complete the required DNS, Outlook, domain, or user cutover tasks for your scenario.

Access Complete Guide

Frequently Asked Questions

Does EdbMails support Office 365 to Office 365 migration between two different tenants?
Yes. Migrating data between any two different Office 365 (Microsoft 365) tenants is exactly what EdbMails Office 365 Tenant to Tenant Migration Tool is built for. It's a common task during company mergers, acquisitions, and corporate restructures, and the cross-tenant workflow is the same regardless of which scenario is driving the migration.
What is Microsoft 365 cross-tenant migration?
Microsoft 365 cross-tenant migration is the process of migrating mailboxes and workloads, including SharePoint, OneDrive, and Teams, from one Microsoft 365 tenant to a separate, independent tenant. It differs from an in-tenant migration because the source and target exist as fully separate Microsoft 365 environments with their own domains and licensing.
Click here to know the steps to perform Office 365 Cross Tenant Migration.
How do I migrate from one Microsoft 365 tenant to another?
At a high level, prepare the tenants, connect the source and target, select and map the supported data, run the migration in planned batches, and validate the target before cutover. See the Office 365 tenant-to-tenant migration step-by-step guide for the complete procedure.
How much time does it usually take to migrate Office 365 tenants?
Migration time depends on data volume, mailbox count, available bandwidth, and Microsoft server response at the time of migration. EdbMails controls throughput through parallel mailbox migration, parallel item processing across multiple threads, automatic throttling management, and full restart/resume support if a job is interrupted. Parallel migration produces the largest speed gain, since migrating several mailboxes between tenants at the same time cuts total runtime compared to a sequential approach.
A few Microsoft-imposed limits affect migration speed regardless of migration tool:
- Individual items are capped at 25 MB by default; this can be increased to 150 MB.
- Throttling policies on both source and target tenants can affect transfer rate.
- The type and volume of data being moved affects speed.
- Network setup at the migration machine affects throughput.
For more detail, refer to this Microsoft article.
To increase throughput on a tenant to tenant project, consider increasing the number of parallel migrations or increasing throttling policy limits in Exchange Online. Learn more about increasing migration speed
Is a Free Trial available to test tenant to tenant migration features?
Yes. The Free Trial lets you test tenant to tenant features before purchase, migrating every mailbox in scope with up to 30 items per folder transferred. That's enough to evaluate mapping behavior, incremental sync and reporting.
Does the software support all languages during migration between tenants?
Yes. Language support applies regardless of source or target tenant locale. Folder names, message body content, and special characters, including accented letters, CJK characters, and right-to-left scripts, are preserved on the target.
What kind of data does the EdbMails Tenant to Tenant migration tool migrate?
The tool covers emails, contacts, calendars, tasks, journals, and notes across primary mailboxes, shared mailboxes, public folders, and archive mailboxes.
Can shared mailboxes, archive mailboxes, and public folders be migrated between tenants?
Yes. Shared mailboxes, In-Place Archive mailboxes, and Public Folders all migrate between Office 365 tenants with their data intact. Public folders carry over with subfolders, mail-enabled folders, items, and permission structure preserved; In-Place Archives keep historical email accessible on the destination; and shared mailboxes arrive with team-collaboration workflows functional on the target from day one.
Can SharePoint, OneDrive, and Teams be migrated between tenants?
Yes. SharePoint Online, OneDrive for Business, and Microsoft Teams are each supported as separate workload migration modules alongside mailbox migration.
Which license do I need for a tenant to tenant migration?
For migrating mailboxes, shared mailboxes, public folders, and archive mailboxes, the Office 365 Migration license is required. Each fresh source email address consumes a license. Public folders consume 50 mailbox licenses, which lets you migrate unlimited public folders from the same domain.
See Office 365 Migration pricing details.
For SharePoint, OneDrive, Teams, Channels, and 1:1 chats, the 'SharePoint + OneDrive + Teams' Migration license is required. The license count is based on the number of source sites for SharePoint and Teams, plus the number of OneDrive users whose data you want to migrate. Buying licenses in bulk saves you more, and any unused licenses stay available for future use.
See 'SharePoint + OneDrive + Teams' Migration pricing details.
Does EdbMails automatically create mailboxes on the target?
Yes, you can choose to let EdbMails automatically create mailboxes on the target Office 365 tenant.
Click here to know more about automatic mailbox creation.

Does EdbMails automatically map mailboxes between tenants?
Yes. EdbMails matches source mailboxes to their target counterparts using user attributes. Automatic mailbox mapping is particularly useful on migrations involving several hundred or several thousand accounts.
Does the software generate duplicates on consecutive runs, and can migration be performed incrementally?
No duplicates. Incremental (delta) migration runs by default from the second migration onward, transferring only items that are new or changed since the last run. Items already on the target tenant stay in place across repeated runs, so consecutive migrations never create duplicates.
Can selective data be migrated from one tenant to another?
Yes. Filtering supports inclusion or exclusion by received date, sender, recipient, CC/BCC fields, subject line, attachment names, and read/unread status.
Are there size limitations for Office 365 tenant mailboxes during migration?
EdbMails does not impose a mailbox size cap for tenant to tenant migration. Microsoft sets platform-level limits that apply regardless of migration tool; refer to this Knowledge Base article for current figures.
Can users continue working during a tenant migration?
Users can continue working in source mailboxes during the data-migration phase. Cutover requirements and any interruption depend on the domain, workload, and migration scenario, so plan the final transition separately.
Is data safeguarded throughout the migration process?
Yes. Migration runs through Microsoft's APIs, with authentication handled by OAuth 2.0 and TLS encryption. Credentials are not exposed during the process. Modern Authentication uses MSAL (Microsoft Authentication Library) and Microsoft Graph, the path Microsoft recommends for tools accessing a tenant.
Does EdbMails support Multi-Factor Authentication (MFA) during Office 365 tenant to tenant migration?
Yes. If Multi-Factor Authentication is enabled on the source tenant, the target tenant, or both, EdbMails works with it natively, with no additional configuration required.
What support options are available for migrating Office 365 tenants?
24/7 technical support is included at no additional cost, available via live chat, email, and phone, with remote sessions for hands-on troubleshooting. User manuals and knowledge base articles cover the migration workflow in depth.
How can mailboxes be migrated between two Office 365 tenants within the same domain?
Same-domain tenant migration requires additional handling because both tenants share the same UPN structure. A dedicated walkthrough covers the same-domain migration steps.
What should I look for in a tenant-to-tenant migration tool?
Start with workload scope, source-to-target mapping, repeat or incremental migration, filtering and batching, authentication and security, and reporting or validation. Confirm workload-specific limitations and licensing before choosing a tool for the production migration.
Does EdbMails provide reports to verify a tenant to tenant migration?
Yes. EdbMails generates detailed migration reports covering the full tenant to tenant migration, with per-mailbox status, folder-level breakdowns, and item counts you can check against the source. This makes it straightforward to confirm every mailbox migrated completely before cutover.

Office 365 Tenant-to-Tenant Migration Tool

Cross tenant Office 365<br> data migration

Just $299 for 100 Mailboxes