How do I get an organizational domain

What is my user ID and why is it needed for Office 365 for business?

Your user ID is assigned to you by your company or school. It looks similar to the following: [email protected], [email protected], or [email protected] This work or school account is made up of your email address and the account you use to sign in to Microsoft 365 Business at your company or school.

Important: If your organization is also signed in to Windows Azure or CRM, or if you've added your domain to one of our online services, you should use the same user ID and domain to sign in and access all of our services.

Your work or school account is different from your Microsoft account. Your Microsoft account is the one you use for personal services like Xbox Live,, Windows 8, Windows Phone, and more. Check out this video, What is a Microsoft Account? for more information.

You can't sign in to Microsoft 365 Business with your Microsoft account at work or at school unless someone in your organization has shared a specific document with you through your Microsoft account. In that case, you can access the document with your Microsoft account.

When you initially get your work or school account, you will also be given a temporary password to log in with. After logging in, you will be asked to create your own password. Use this password along with your user ID every time you sign in to Microsoft 365 Business. For more information about how to change your password, including how to create a strong password, see I forgot the username or password for the account I use with Office.

Microsoft 365 business administrators

The following information is intended for Microsoft 365 Business administrators only.

Create new user accounts

You create a new user ID with a unique username for each account that you add to the subscription. The domain part of your user ID is either the domain that you selected when you signed up for Microsoft 365 Business, or another domain, e.g. For example, your organization's custom domain that you added in Microsoft 365 Business.

For example, if you selected as your domain name when you created your account and you are creating a user account with the user name "colin", your user ID would be [email protected]

If you'd like to use your custom domain for user IDs and email addresses, see Verify your domain in Microsoft 365.

Set up and use an alternative email address

When you sign up for Microsoft 365 Business, you must also provide an alternate email address that is not associated with Microsoft 365 Business. This email address is used for important notifications like resetting your admin password so you need to access the email account if you don't have access to Microsoft 365 Business. After the sign-in process is complete, you will receive an introductory email to your alternate email address containing your user ID and the URL of the web page on which you are going to sign in to Microsoft 365 Business. If you forget your User ID or can't remember the Microsoft 365 Business URL, find this information in the introductory email.

Note: The alternate email address that you must provide during the login process is used for important information such as resetting administrator passwords. Any product-related information that you would like to receive from Microsoft 365 Business will also be sent to this email address, unless you change your contact settings. You can change your contact settings on the page I To update. For more information on changing your contact settings, see Change your contact settings.

See also

Where can I sign in to Microsoft 365?

Note: This page has been translated automatically and may contain grammatical errors or inaccuracies. Our goal is to provide you with helpful content. Please let us know if this information was helpful to you. Here you can find the English article for reference.