IT Partner provides planning, design, and migration of email service from one Microsoft 365 tenant to another. This service is usually needed when a company merges with or acquires another company, when both organizations use Microsoft 365, or when an organization wants to migrate to a different geographic region.
Occasionally, a customer needs a migration inside the Microsoft 365 cloud platform. For example, if one company acquires another company and both are using Microsoft 365, there may be many reasons to start merging. This service provides planning, design, and migration of email service from one Microsoft 365 tenant to another. While the domain is transferring from the source tenant to the new tenant, incoming mail will not be received for about 24 hours because of domain name binding features in Exchange Online. To avoid loss of emails during the transfer period, you can consider the extended migration service. This workload is one part of our end-to-end Microsoft 365 Tenant-to-Tenant Migration program, which quotes the whole move from the inventory.
Confirm business objectives, migration scope, source and destination tenant details, key contacts, mailbox count, high-risk users, cutover window, communication approach, and decision-making process for the tenant-to-tenant cutover.
Review the source tenant and destination tenant readiness, including domains, accepted domains, mail flow, mailbox sizes, licensing, Exchange Online configuration, DNS access, transport rules, and known risks that could affect the migration.
Prepare destination identities and mail objects by creating or synchronizing users, assigning required Exchange Online licenses, importing contacts and groups as applicable, and validating that target mailboxes or mail-enabled objects are ready for migration.
Configure the migration approach and begin the pre-stage migration for eligible mailbox content, focusing on emails and email folders older than 30 days, while monitoring migration progress and addressing initial errors.
Validate pre-stage migration results by checking selected mailboxes, folder structure, item counts where available, migration reports, and any failed or skipped items that require remediation before cutover.
Coordinate the cutover window and update required public DNS records, including the MX record and related mail flow records as required, so inbound mail is directed to Exchange Online in the destination tenant.
Perform the final migration pass to move recent mailbox data and remaining mailbox content, including calendars, contacts, rules, and other in-scope mailbox data, then confirm completion status for migrated users.
Validate user access, inbound and outbound mail flow, and required transport rules in the destination tenant; assist with migration-related issue review; and prepare the project closeout report.
IT Partner’s Microsoft 365 tenant-to-tenant cutover email migration service plans, designs, and migrates email service from one Microsoft 365 tenant to another. It is commonly used after mergers and acquisitions, when both organizations already use Microsoft 365, or when a company needs to move email to a tenant in a different geographic region.
The service includes exporting mailbox-enabled users, contacts, groups, and related resources from the source tenant, then importing them into the destination tenant by Microsoft Entra Connect or CSV import. It also includes pre-stage migration of emails and email folders older than 30 days, final mailbox migration of calendars, contacts, rules, and other mailbox data, required domain zone record changes for the migration, and a project closeout report.
The service does not include informing users about upcoming changes, customer team training, migration of corporate documents to SharePoint Online, or desktop software settings. More extensive documentation than the project closeout report, customer training, and SharePoint Online document migration can be provided only as additional services if agreed with IT Partner.
Before the migration starts, global admin level access is required to both the source Microsoft 365 tenant and the destination Microsoft 365 tenant. The destination tenant must have available Exchange Online licenses, and access to the email domain DNS zone is also required because domain and mail flow records must be changed during the migration.
The project typically includes a kickoff meeting, a source system health check, user creation or Microsoft Entra Connect configuration, email migration start, migration verification, MX record change to the new Microsoft 365 tenant, final email migration, and post-migration tasks. The exact plan may vary depending on customer needs and the state of the source and destination tenants.
Yes, incoming mail will not be received for about 24 hours while the domain transfers from the source tenant to the destination tenant. This is due to domain name binding behavior in Exchange Online, so customers should plan for a mail flow impact during the cutover window.
The standard cutover service notes that incoming mail will not be received for about 24 hours while the domain transfers between tenants. To avoid losing email during that window, consider the Microsoft 365 Tenant-to-Tenant Cutover Email Migration Without Downtime service, which is designed to keep mail flowing during the transfer.
The client must provide a dedicated point of contact, coordinate outside vendors and schedules, configure network equipment if needed, deploy email software on client workstations if Microsoft Outlook or other desktop email clients are used, perform changes to internal and external DNS as required, and identify high-risk users such as executives, VIP users, or users with very large mailboxes. The client is also responsible for informing users about upcoming changes and recreating new Outlook profiles on client workstations if desktop Outlook is used.
Yes, if users connect with the desktop version of Microsoft Outlook, the client is responsible for recreating new Outlook profiles on all client workstations. Desktop software settings are outside the included migration scope.
No. Exchange Online Protection configuration is not part of tenant-to-tenant migration work — the destination tenant keeps its existing protection settings, and moving mailboxes does not change how mail is filtered. If you need EOP reviewed or configured in the destination tenant, that is scoped as separate work.
The listed service duration is 5 weeks. Actual timing depends on tenant readiness, mailbox sizes, DNS coordination, and migration complexity, and is confirmed during kickoff planning.
The service is priced at $35 per mailbox plus a $3,500 tenant fee, quoted in writing before work begins — you pay after you approve delivery. Additional services, such as customer team training, SharePoint Online document migration, or more extensive documentation, are quoted separately.