Can I have more than one email account with the same ID?

Your Email Address IS Your Account ID

On 99% of the email systems we deal with every day, your email address is your account ID. If you want a different email address you create a new account. If you need to switch accounts you'll end up with a new email address.

Email address and "accounts" are inseparable because they're really the same thing most of the time.

Let's say you have an email address example@hotmail.com and you don't like it - you would rather have notanexample@hotmail.com - the answer is simple: you create a new account. There's no relationship between old and new. You can't change the email address of the account because the email address is the account. A new email address is a new account.

And yes, that may be a hassle if you're using a web interface to access your email and want to transfer messages and contacts from one account to another. But it is what it is.

In fact, that Hotmail email address is actually your account ID for a whole host of services from Windows Live, including Messenger, Spaces, Skydrive and much more - you login once using your email address as your ID, and you have access to all those services, not just Hotmail.

The same is true for other services as well, including Google, Yahoo and many others.

Email address is account ID. Account ID is email address. Can't change one without the other. Make a new one, you've made a new of the other as well.

Exception 1

Some ISPs give you a separate login to access their network which is your account ID, and then allow you to associate some number of email addresses from that ISP with that ID. I've only ever seen this with ISPs, and even then it doesn't appear to be very common.

I'm almost willing to bet that this is not your situation, particularly if we're talking on-line services like Hotmail, Gmail and the like.

Exception 2

Some email services allow you to add an identifier to your email address that makes it look like a different email address, but still routes to the same account.

For example I might have:

leo@somerandomservice.com

And when subscribing to a newsletter I might use:

leo+askleo@somerandomservice.com

Both are the account "leo@somerandomservice.com", and both are delivered to the same inbox.

Not all services actually provide this functionality - in fact it remains fairly rare. Check with your email service provider if they do anything like this.

Alternatives

As I said, I don't know what specific problem you're attempting to solve, but I'll throw out two very common solutions to the kind of division you're talking about:

• An Additional Account: Even though it would be creating an additional "ID", to use your terms, creating an additional email address and account is often the easiest and most expeditious solution to this kind of problem. Separate email accounts typically mean separate inboxes, but you can also use desktop email programs to download email from multiple accounts and process them however you like. Which actually leads to the second possible solution:

• Filter Incoming Mail: Most desktop email programs, and some web services, allow you to filter or take action on email as it arrives. The solution that comes to mind here is to pick some characteristic of incoming email and automatically route that email to sub folders that you've set up. Perhaps email with the word "Question" in the subject line would automatically get placed in the "Questions" folder, while email from certain people would get placed into some kind of "VIP" folder. There are quite literally unlimited possibilities here. In desktop email programs, look for "filters" or "rules". Gmail includes filters which allow you to place labels on email based on criteria you specify to the same effect.

  And of course if you do use your desktop email program to access more than one email account as in the first suggestion, or the different email addresses on the same email account as in the second exception, you can always use filters to route each account's email into its own folder.

Hopefully one of those suggestions will address your specific situation.

Preemptive warning ('cause I know it's coming): comments to this article that ask how to change an account's email address will be deleted. Please re-read the article.