You may have a number of different email addresses and keeping them straight can be a handful. One of the confusing points is whether an email address is a mailbox or a domain alias. Let’s examine the difference.

Email Box: Imagine an email box like a physical mailbox you have at home.  It’s a place where emails are stored and organized for you to access.  When someone sends you an email, it gets delivered to your email box, and you can check it whenever you want.  Mailbox addresses end with the domain of the mail provider. Some common examples are,,, or The company you work for may have it’s own mail server and if it does that is your mail provider.
Domain Aliases: These email addresses are alternate ways to get to an email box. They do not have their own storage area. Think of it like this. Suppose you’re a well known author.  Your fans can write to you, care of your publishing company, and your publishing company will send the letters along to you without your fans ever knowing where you actually live. Domain aliases work like that.

Aliases also allow you to redirect messages to several mailboxes.  For example, if you have a role email address, like, that can be sent to several people in your company that handle support requests. 

When you register a domain for a website, it is also available to use for domain aliases.

There are lots of reasons to have domain aliases. It will make your company look more professional. If you change your mail host you don’t need to notify the people you communicate with.  They will continue to use your domain alias which will now point to a new email box.

In summary: An email box is a personal inbox where emails are stored for a specific email address. A domain alias is an alternate name for an email box. An email box has physical space associated with it; a domain alias does not.