How do I add a sub account (not an email address) to an existing Outlook account?

To add a separate Outlook account for maintaining dual identities without switching back and forth between email addresses, you can create a new Microsoft 365 account for the additional identity. Here’s how you can do it:

1. Create a New User Account: You will need to have administrative privileges to create a new user account in your organization's Microsoft 365 admin center. This account will serve as the separate Outlook account.
   • Go to the Users > Active users page in the admin center.
   • Click on Add a user and fill in the necessary details for the new account.
2. Set Up Outlook: Once the new account is created, you can set it up in Outlook:
   • Open Outlook and select File > Add Account.
   • Enter the new email address and follow the prompts to complete the setup.
3. Sign In with Different Accounts: You can now sign in to Outlook with both accounts. Each account will maintain its own settings, signatures, and email addresses, allowing you to keep them truly separate.
4. Switching Accounts: You can switch between accounts in Outlook by selecting your profile icon in the top right corner and choosing the account you want to use.

This setup will help you avoid the issues related to shared signatures and the need to select which email to use each time you send an email.

References:

• Add another email alias for a Microsoft 365 business subscription user
• Understand licensing in new Outlook for Windows

Hi @Jessi Schmidt,

Welcome to the Microsoft Q&A forum.

Thank you for reaching out regarding the need to maintain distinct identities within Outlook. We understand the importance of keeping email addresses, signatures, and sending options clearly separated to reduce complexity and minimize errors.

After testing the steps provided in the Q&A assist, the solution appears to work in my test environment, and I would like to include an additional step for completeness. You can try this approach and let us know if it works for your situation. If not, please inform us so we can explore alternative options or if you need assistance with any of the steps.

An additional step you can take after completing steps 1 through 3 in the Q&A assist is to configure separate signatures for each account. Here's how:

Open the new Outlook > Click the setting (gear) icon at the top right

Go to Accounts > Signatures, then select the expand arrow and choose the account for which you want to edit the signature.

Scroll down and select the default signature for each account > Save

From then on, whenever you compose a new email, select the correct account in the From field, and its associated signature will automatically populate.

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.   

Thank you for your patience and your understanding. If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you.

I look forward to continuing the conversation.

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