Can I add custom subdomains or multiple domains to Office 365?

Most Office365 plans include the same features for domains. For example, you can add multiple custom domains, add subdomains, and decide whether you want to manage DNS for a custom domain yourself or have Office365 manage DNS for the domain.

Review the information below to understand how you can use Office365 in your organization. The Office365 domains service description includes an even more detailed list. You can also review the overall product features of each offering.

  • You can add multiple domains or subdomains. For example, you could add the domains and, and then add the subdomains,,, and so on. How? You add additional domains or subdomains the same way you added your initial custom domain, by following the steps in the domains setup wizard.
  • When you add multiple domains to Office365, you can host any of the services (like email) on any of the domains you’ve added.
  • If you already have a public website that you use with your domain, when you add your domain to Office365, you can keep hosting your current website where it is hosted now without taking extra steps.
  • Set up your domain in Office365, and in the domains setup wizard, be sure to choose Yes when asked if you have a website you’re already using. Then you add and update your DNS records on your DNS hosting provider website to configure the DNS records for services, such as email and Skype for Business Online.
  • Choose how you’ll manage DNS for your domain. You can continue to manage your DNS records at your DNS hosting provider (or on premises, if you manage your own DNS file locally)—for example, to add or update MX or CNAME records. Or you can have Office365 set up and manage DNS records for your domain. You’ll have the option to choose how to manage DNS records when you step through the domains setup wizard.

Note: If you’re adding a subdomain, like, you must manage DNS for the domain outside of Office365.

If you choose to have Office365 create and host your domain’s DNS records, email and IM are automatically set up to use your domain, hosted by Office365, and you can’t host email or IM with another hosting provider. You also cannot add a subdomain of your domain unless you first change DNS management to a DNS host outside Office365 for your domain.

If you choose to manage DNS for your domain yourself, you can set up email, IM, and your public website to use your domain in Office365, or you can host some (or all) of those services on your domain with another provider.

More about how domains work with Office365 services

Post Author: Cody Romero