Office Support / Office 365 Admin / Domains

Work with domain names in Office 365

When you sign up for Office 365, you’re given an initial domain name that looks like The domain name is part of your user ID, like, and you can use the domain to try out Office 365 services. Or you can use a custom domain name for user ID, and email and other services.

You can add a custom domain, but you can’t rename the initial domains. For example, if the initial domain you chose during Office 365 signup was, you can’t change it to be To use a different, you’d have to open a new account with Office 365. And, unfortunately, you can't use your custom domain for team site addresses.

Use your own domain with Office 365

To use your own domain with Office 365, instead of the domain that you were given at signup, you can add your domain to Office 365 following the steps in the domains setup wizard. After Office 365 confirms that you own the domain, you can use user IDs and email addresses, like instead of Learn more about setting up and managing your domain with Office 365.

You can continue to use your and domains if you like, even after you add your own domain name to Office 365, and email still works with your domain.

Consider the following before you set up your own domain to use with Office 365.

  • You must own a domain before you can set it up in Office 365. If you don’t yet own the domain that you want to add, you can register the domain at a domain name registrar.

  • You can add a domain with any name that is currently available. The name doesn’t have to match the first part of your domain. For example, if your domain was named, you could add a custom domain named

  • You can’t add a domain that you’re already using in another Microsoft cloud service.

  • Before you can confirm to Office 365 that you own a domain, you must have the sign-in credentials for your domain registrar or DNS hosting provider. If you don’t remember where your DNS records are hosted, you can learn more about finding your domain registrar or DNS hosting provider.

Need help with a domains issue?

Use a custom domain name to rename your Office 365 public website

After you add your custom domain, get Office 365 email in Outlook

Get the MX record to set up your email on your domain

Find step-by-step instructions for setting up DNS for your domain in Office 365

Learn about how DNS is managed in Office 365

Get help with Office 365 domains

Still need help?

Get help from the Office 365 community forums Admins: Sign in and create a service request Admins: Call Support

Applies To: Office 365 Admin, Office 365 Small Business Admin

Was this information helpful?

Yes No

How can we improve it?

255 characters remaining

To protect your privacy, please do not include contact information in your feedback. Review our privacy policy.

Thank you for your feedback!

Change language