Why add a domain in Office 365?

Adding a custom domain, like fourthcoffee.com, to Office 365 lets you use a shorter, more familiar email address and userID with the service. You're given a domain to use when you sign up for a Office 365 account, but it includes "onmicrosoft.com." Many people prefer to add their organization or business domain if they plan to use Office 365 for email.

If you just want to download and use Office 365 apps, like Outlook or Word, you don't need to add a domain: Install Office on your PC or Mac.

You can use your domain name in Office 365 with your email, public website, and instant messaging address.

  • Email: Your domain name lets you customize your email, so you can use a shorter, easier-to-remember address than the initial onmicrosoft.com email address that comes with your account. So instead of joe@contoso.onmicrosoft.com, the email address (which is also the work account that you use to sign in to Office 365) could be joe@contoso.com.\
  • Website: If you have an Office 365 subscription that includes a SharePoint Online Public Website (no longer available for purchase), your public website comes with an initial address like this: contoso-public.sharepoint.com. If you set up your website for your business, you can use a custom domain name to rename the website address to something like www.contoso.com.
  • Instant messaging: Your Skype for Business Online address can also be customized to use your domain name, so people in your organization can connect with each other on Skype for Business Online by using a shorter, easier-to-remember address (like joe@contoso.com).


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