What you can and cannot change in Office 365

Office 365 has two different usernames, and which one you can change depends on whether your account is personal or managed by an organization. Your Microsoft account username (the email address you use to sign in) can be changed if you set up the account yourself. Your display name (what appears in Outlook, Teams, and shared documents) can almost always be changed, even if your organization manages your account.

If your company, school, or institution manages your Office 365 account, you cannot change the email address you sign in with — only your IT department can do that. However, you can still change how your name appears to other people in Office 365 apps. This guide covers both scenarios.

Key Takeaways

  • Your display name (what others see) can be changed in account settings even if your organization manages your account.
  • Your sign-in email address can only be changed if you own the account personally, not if an organization manages it.
  • Changes to your display name take effect when ready in Outlook and Teams, but may take a few hours to appear everywhere.
  • If your organization manages your account and you need to change your sign-in email, contact your IT department or help desk.

Change your display name in Office 365

Your display name is what appears next to your messages in Outlook, Teams, and when you share documents. To change it, sign in to your Microsoft account at account.microsoft.com. Click Your info in the left menu, then look for the section showing your name at the top of the page.

Click on your name to edit it. You can change your first name, last name, or both. Type the new name and click Save. The change takes effect right away in most Office 365 apps, though it may take a few hours to appear in shared documents or email you sent before the change.

If you use Office 365 through work or school, you may see a message saying your display name is managed by your organization. In that case, you can still try clicking Edit next to your name — some organizations allow employees to change their own display name even though they control the sign-in email. If the edit button is grayed out, contact your IT department.

Change your sign-in email address (personal accounts only)

If you own your Office 365 account personally and want to change the email address you use to sign in, go to account.microsoft.com and click Your info. Look for the section labeled Email addresses or Account aliases. You may see multiple email addresses listed — one is your primary sign-in address, and others are aliases you can use to sign in as well.

To change your primary sign-in email, click Manage how you sign in to Microsoft or Change email address (the exact wording varies). You will be asked to verify your identity, usually by entering a code sent to your current email or phone number. After verification, you can enter a new email address. Microsoft will send a confirmation link to that new address — click it to complete the change.

The new email address becomes your primary sign-in when ready, but you may need to sign out of Office 365 apps and sign back in with the new email for the change to take full effect. If you have Office installed on your computer (not the web version), you may need to update your credentials in the app settings as well.

Update Office 365 apps after changing your username

If you changed your sign-in email address, you need to update it in any Office apps installed on your devices. On Windows, open any Office app like Word or Excel, click File, then Account. You should see your email address listed. If it still shows the old email, click Sign out, then Sign in and enter your new email address.

On Mac, open any Office app, click the app name in the menu bar (for example, Word), then Preferences. Look for Account or Sign in and update your email there. On phones and tablets, sign out of the Office app, then sign back in with your new email address.

If you only changed your display name and not your sign-in email, you do not need to update anything in your apps — the display name change happens automatically across all Office 365 services within a few hours.

What to do if your organization manages your account

If you work for a company, attend a school, or use Office 365 through an institution that manages your account, you cannot change your sign-in email address yourself. Your organization's IT department controls that email and can only change it through their admin tools. Contact your IT help desk or support team and explain that you need your sign-in email changed. They will ask you why and may need approval from a manager or administrator before making the change.

You can still change your display name on your own, as described above. If the edit button is locked, your organization has restricted that too — in that case, ask your IT department to change your display name for you, or ask them to unlock the setting so you can change it yourself.

Troubleshooting common problems

If you changed your display name but it still shows the old name in Teams or Outlook, wait a few hours and refresh the app. Close the app completely and open it again, or sign out and sign back in. If the old name persists after 24 hours, try clearing your browser cache if you use the web version of Outlook, or uninstall and reinstall the app on your computer.

If you changed your sign-in email but cannot sign in with the new email, make sure you are using the exact email address you entered — check for extra spaces or typos. If you still cannot sign in, go to account.microsoft.com, click Security, and look for Recent activity to confirm the email change went through. If the change did not save, try again from a different browser or device.

If you see a message saying your account is locked or suspended, do not try to change your username. Instead, go to account.microsoft.com and look for a security alert or recovery option. You may need to verify your identity by answering security questions or entering a code sent to a backup email or phone number.

Frequently Asked Questions

Can I change my Office 365 username if my company manages my account?

You can change your display name (what others see), but not your sign-in email address. Only your IT department can change the email you use to sign in. Contact them if you need that changed.

How long does it take for a display name change to show up everywhere?

Display name changes take effect when ready in Outlook and Teams, but may take a few hours to appear in shared documents, email signatures, or other Office 365 services. If it has been more than 24 hours, try signing out and back in.

Do I need to change my password when I change my username?

No. Your password stays the same. If you changed your sign-in email address, you use the new email with your existing password to sign in.

What happens to my old email address if I change my sign-in email?

Your old email address becomes an alias that you can still use to sign in, or your organization may remove it entirely. Check your email aliases in account settings to see what addresses are still active.

Can I change my username back if I made a mistake?

Yes. Follow the same steps to change your display name or sign-in email again. If you changed your sign-in email and want to switch back, you can make the old email your primary again through account settings.