Please follow instructions based on the version of MS Outlook you are using, Classic (Older) Method 1 or New version Method 2..
Method 1. Adding a secondary Microsoft 365 email account to the New Outlook version.
New Version Icon looks like this:
Adding as a New Email Account
This method is for adding a completely separate 365 email account that you have full login credentials for.
- Open New Outlook:
- Launch the New Outlook application on your computer.
- Access Settings:
- In the top right corner of the Outlook window, click on the Settings gear icon.
- Go to Accounts:
- In the Settings pane, select Accounts > Email accounts.
- Add Account:
- Under the "Email accounts" section, click on Add Account.
- Enter Email Address:
- A dialog box will appear.
- Enter the full email address of the secondary Microsoft 365 account you want to add and click Continue.
- Enter Password:
- If prompted, enter the password for that email account and click Done or Sign in.
- Complete Setup:
- Outlook will attempt to configure the account automatically.
- Follow any additional on-screen prompts to complete the setup.
Once added, the secondary account will appear in your left-hand navigation pane, and you'll be able to access its folders, send emails from it, and manage its settings.
Method 2. Adding a Separate Microsoft 365 Email Account (with its own login) to the Classic Version of Microsoft Outlook
Classic Version icon looks like this:

This method is for adding an entirely separate 365 email account that you have distinct login credentials for.
- Open Classic Outlook:
- Launch the Classic Outlook desktop application.
- Go to File Tab:
- In the top-left corner of the Outlook window, click on the File tab. This will open the "Backstage view."
- Click "Add Account":
- Under "Account Information," you'll see a large button that says + Add Account. Click on it.
- Enter Email Address:
- A new window will appear.
- Enter the full email address of the secondary Microsoft 365 account you want to add and click Connect.
- Enter Password:
- Outlook will likely try to auto-discover the settings.
- If prompted, enter the password for that email account and click Sign in or OK.
- Multi-Factor Authentication (MFA):
- If your organization uses MFA, you may be prompted to complete a second verification step (e.g., approve a notification on your phone, enter a code from an authenticator app, or use a security key).
- Complete Setup:
- Follow any additional on-screen prompts.
- Outlook should successfully configure the account.
- Finish:
- Once the setup is complete, click Done or Finish.
- You may be prompted to restart Outlook for the changes to take effect.
After restarting, the new account will appear in your left-hand navigation pane, and you'll be able to access its folders, send emails from it, and manage its settings.