Office Support / Office 365 Admin / Domains

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

Most Office 365 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 Office 365 manage DNS for the domain.

Review the information below to understand how you can use Office 365 in your organization. The Office 365 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.

  • When you add multiple domains to Office 365, 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 Office 365, you can keep hosting your current website where it is hosted now without taking extra steps.

    Set up your domain in Office 365, 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 Office 365 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 Office 365.

    If you choose to have Office 365 create and host your domain's DNS records, email and IM are automatically set up to use your domain, hosted by Office 365, 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 Office 365 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 Office 365, or you can host some (or all) of those services on your domain with another provider.

More about how domains work with Office 365 services

  • In most circumstances, you can add up to 900 domains to your Office 365 subscription. If you're planning to use many domains, see Using a large number of domains with Office 365.

  • Office 365 creates a domain for you when you sign up with the service, like You can keep using this domain for your user ID and for your Office 365 services, or add your own custom domain.

  • You can use any custom domain name that is available at your domain name registrar. It doesn’t have to match the first part of your domain. For example, if you signed up for Office 365 using, you could use,, or a completely different name like

Learn more at Get help with Office 365 domains.

Still need help?

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

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