want to change the username and domain

Question

want to change the username and domain

Melanie Fernandes 0

I want to change the username and domain that I currently have and change it to my company email address

Lin V 2,055 Reputation points Independent Advisor

2026-11-13T19:58:45.91+00:00

Hi Melanie,Just checking in to see if you've reviewed the proposed answer. Any update would be appreciated.

2 answers

Your answer

Lin V 2,055 Reputation points Independent Advisor

2026-11-13T19:58:45.91+00:00

Hi Melanie,Just checking in to see if you've reviewed the proposed answer. Any update would be appreciated.

Answer 1

Change the account in the Microsoft 365 admin center by editing its username and selecting your company’s already-verified domain.

Change the username and domain

Sign in to the Microsoft 365 admin center.
Go to Users → Active users.
Select the account you want to change.
On the Account tab, select Manage username and email.
In Username:
- Enter the required part before @.
- Select your company domain from the Domains list.
Select Done. These steps require at least the User Administrator role.^1^
Sign out of Microsoft 365, then sign back in using the new company email address.^2^

For example:

Current account: [Email]
New account: [Email]

The original onmicrosoft.com tenant domain remains part of Microsoft 365; changing the user’s address does not rename or remove that tenant domain.

If you also want to change the displayed name

The display name is managed separately:

Go to Users → Active users.
Select the user.
Under Account, select Manage contact information.
Update the display name and select Save changes.^1^

If the account is synchronized from local Active Directory

If the page reports that the user is synchronized with local Active Directory and some details can only be edited there, do not change it in Microsoft 365. Change the username/UPN in the on-premises directory and allow directory synchronization to update Microsoft 365.

Microsoft notes that changing the UPN does not change the account’s Microsoft Online Email Routing Address (MOERA), although the sign-in UPN should generally match the primary SMTP email address.^1^

If the change fails

“We’re sorry, the user couldn’t be edited”: the signed-in administrator does not have the required admin role.
“A parameter cannot be found that matches parameter name 'EmailAddresses'”: if the custom domain was added recently, setup can take up to four hours. Wait and retry; if it persists, contact Microsoft 365 support and request a full synchronization.^1^
If the account must send and receive mail through the company domain, it needs an Exchange-enabled license.^2^

References

Answer 2

Hi Melanie,

If you purchased a Microsoft 365 Business subscription and currently have an .onmicrosoft.com account/domain, you can switch to your company email address by following the steps below.

Note: These actions must be performed by an Admin. To check if you have admin permissions, try signing in to the Microsoft 365 admin center. If you can access the dashboard, you are an admin.

1/ Add your company domain to your Microsoft tenant

Before changing your email address, you need to connect and verify your custom domain in Microsoft 365.

Sign in to the Microsoft 365 admin center.
In the left navigation menu, go to Settings > Domains.
Select Add domain, enter your company domain name (e.g., yourcompany.com), and click Use this domain.
Verify ownership: Microsoft will generate a TXT record (or MX record). Log in to your domain registrar and add this record to your DNS settings.
Return to the Microsoft 365 admin center and click Verify.

Follow the remaining on-screen instructions to add the required DNS records (MX, CNAME, TXT) so your emails route properly through Microsoft 365.

For reference: Add a custom domain to Microsoft 365

2/ Change your username and domain

Create your new company email as an alias on the same account first, and then promote that alias to your primary email address. This ensures you continue receiving emails sent to your old .onmicrosoft.com address without interruption.

In the Microsoft 365 admin center, go to Users > Active users.
Click on your user account from the list.
Under the Account tab, locate the Aliases section and select Manage username and email.
In the Username field, enter your desired name prefix, select your newly added company domain from the dropdown list, and click Add.
Once the new company address appears in your list of aliases below, click the ... (More actions) icon next to it and select Change to primary email.
Click Save changes at the bottom

I hope this information is helpful. Let me know if you have any questions.