How to Merge Office 365 Accounts?

Published On - December 24, 2025 by Nasir Khan | Reading Time: 4 minutes

Microsoft Office 365 is widely used for managing emails, calendars, contacts, and collaboration tasks. Over the period, users may create multiple Office 365 accounts due to job changes or organization restructuring. Handling multiple mailboxes separately often leads to confusion and missed communication.

To simplify email management, many users choose to merge Office 365 accounts into a single mailbox. Although Microsoft does not provide a built-in option to merge accounts directly, there are manual and professional methods available. This blog explains why users merge Office 365 accounts and how to do it safely without losing data.

What Does Office 365 Accounts Merge Mean?

Merging Office 365 accounts means moving emails, contacts, calendars, and other mailbox data from one Office 365 account to another. After merging, all data can be accessed from one account.

Methods to Merge Office 365 Accounts:

There are mainly two ways to merge Office 365 accounts. Below, we have covered both manual and automated professional methods.

Method 1: Merge Office 365 Accounts Using Outlook (Manual Method)

Step1: Add Both Office 365 Accounts to Outlook

1. Open Microsoft Outlook
2. Go to File → Add Account
3. Add both Office 365 accounts using their credentials

Step2: Export Emails from the Source Account

1. Click File → Open & Export → Import/Export
2. Choose Export to a file.
3. Select Outlook Data File (.pst).
4. Select the source mailbox and export it.

Step3: Import PST into the Destination Account

1. Open Outlook with the destination account.
2. Go to File → Open & Export → Import/Export.
3. Choose Import from another program or file.
4. Lastly, select the PST file and import data.

Limitations of Manual Methods:

1. Very time-consuming and requires high technical knowledge.
2. It is not suitable for professionals, as a large mailbox size can be a problem.
3. High chances of data loss or structure loss.
4. There is a high risk of losing important files or data corruption.
5. You will not get any advanced option to customize the data transfer.

Method 2 – Professional Solution ( Regain Office 365 Migration Tool)

The Regain Office 365 Export Tool is a one-stop solution to manage and merge Office 365 accounts. This tool allows users to merge multiple Office 365 accounts into one single mailbox without losing emails, attachments, folders, or formatting by migrating mailbox data from one account to another.

Free Download100% Secure Buy NowPrice: $89

Some of the highlights of this utility are:

• Migrate Office 365 mailbox data to a new Office 365 mailbox, Exchange On-Premises mailbox.
• It can also migrate data from Exchange On-Premises to Exchange Online (Office 365).
• Export Exchange Online to any IMAP Email client or Server like Gmail, Yahoo! Mail, Zoho, Yandex.
• Also capable of exporting data from Exchange Online to PST, MBOX, EML, MSG, ICS, VCF and PDF.
• No limitations on the size and number of Office 365 mailboxes.
• A free demo version and 24*7 lifetime technical support to assist users.

Steps to Merge Office 365 Accounts Data:

To perform this migration process, you need to follow some simple steps, which are as follows:

1. Firstly, install and launch the Regain Office 365 Export Tool.
2. You will see the option of Account Log in to connect to a Microsoft 365 account. The software supports both Basic and Modern Authentication. Enter the asked credentials.
3. The software will now provide a preview of the mailbox data.
4. Now, select the Cloud Migration option from the ribbon bar and select Office 365 as the target.
5. Again, connect with the target Microsoft 365 account. Map the mailboxes and start exporting data. In this way, you can merge the Office 365 accounts.

After exporting the data from the old account, you can change the MX record and suspend the account address which is not in use.

Wrapping Up:

Merging Office 365 accounts helps users manage emails in one place and avoid confusion. Manual methods are available but take time and carry risks. For a smooth, fast, and safe process, the Regain Office 365 Merge Tool/ Office 365 Export Tool is the best choice.

With the right approach, you can easily merge Office 365 accounts without losing any important data. Try the free demo version of the software.

Frequently Asked Questions:

Q1. What will be the hierarchy of the mailbox data after merging the accounts?
A. The software exports data from one mailbox to another target mailbox with the maintained folder hierarchy.

Q2. I don’t want to merge all folders. Is there any way to manage them?
A. Yes. With Regain’s utility, you can unselect/uncheck the folders that you don’t want to merge.

Q3. Is there any way to test this utility before purchasing the license?

A. Yes. The software offers a free demo version. You can test the compatibility of this utility before making any purchase. The demo version upgrades to the full version after applying the license.

Q4. It seems a little bit complicated. Can I get any kind of technical assistance if I need it?

A. We provide 24*7 free technical assistance. If you need any kind of technical assistance, feel free to contact Regains’ support team.