What is a domain?

Check the Domains FAQ if you don't find what you're looking for.

A domain is a unique name that appears after the @ sign in email addresses, and after www. in web addresses. It typically takes the form of your organization's name and a standard Internet suffix, such as yourbusiness.com or stateuniversity.edu.

Using a custom domain like rob@contoso.com with Microsoft 365 can help build credibility and recognition for your brand.

Choose the experience that's best for you:

Buy a new Domain:

Use Microsoft 365 to buy a new domain - we'll set everything up. Learn more.

Use a domain you already own:

If you already own a domain like you@yourcompany.com you can add it and start using OneDrive and Microsoft apps right away. You'll need to take a few minutes to setup mail and Skype for Business.


Not sure where your domain is registered? - Get help finding your domain registrar

Use a default domain for now:

You can use a default domain like yourcompany.onmicrosoft.com to log in for now and add a custom domain later. You can't change or rename your default domain - so make sure it's what you want before moving on.

Feeling stuck?

Call Microsoft Support - Get help setting up a domain