Did you create a Mac user account with an incorrect name, perhaps making a typo during setup? Are you tired of that user name that sounded cute a few months ago, but is now so yesterday? No matter the reason, it's possible to change the name used on your Mac's user account and home directory.

If you're scratching your head at this point, because of the popular misconception that account names are set in stone, and the only way to change a name is to create a new account and delete the old one, then have I got a tip for you.

You can change the short name, home directory name, and even the full name of a user account.

Basic Mac User Account Information

Each user account contains the information below; well, actually there's more information that goes into a user account, but these are the three aspects we're working with here:

• Full Name: As you've no doubt guessed, this is the user's full name. It can be also be used as the login name. For example, Tom Nelson.
• Short Name (also called the Account Name): This is a shortened version of the full name; for example, tnelson. Your Mac will actually suggest a short name based on the full name you entered, but you can use any name you wish. The short name will also be used as the name of the home directory, as well as the login name.
• Home Directory: As I mentioned already, the Home Directory and the Short Name will be the same. They must remain the same at all times for your user account to work correctly. The Home Directory is usually located in the Users directory of your startup drive, but you can actually relocate the home directory to just about anywhere you wish.

Changing Account Information

If you made a typo when setting up a user account, or you simply wish to change the name, you can do so by following the instructions below. Just remember that there are certain limitations, the most important being that the Short Name and Home Directory name must match.

If you're ready to change your account information, then let's get started.

Back Up Your Data

This process is going to make some fundamental changes to your user account; as a result, your user data could be at risk. Now that may sound a bit over the top, but it's possible for a problem to occur during the process of making changes that could cause your user data to become unavailable to you; that is, its permissions could be set in such a way that you no longer have access to it.

So, before beginning, I highly recommend taking the time to ensure that you have a current backup. If possible, create both a current Time Machine backup and a bootable clone of your startup drive. 

With the backup out of the way, we can continue.

Change Account Short Name and Home Directory (OS X Lion or Later)

If the account you're going to be changing is your current administrator account, you will need to first have a different, or spare, administrator account to use during the process of changing account information.

If you don’t already have an extra admin account, follow the instructions in:

Create a Spare User Account to Assist in Troubleshooting

After you create a spare administrator account to use, we can begin.

1. Log out of the account you wish to make changes to, and log into your spare administrator account.
2. Navigate to the /Users folder located on your Mac's startup drive.
3. Within the /Users folder you'll see your current home directory, with the same name as the account's current short name.
4. Write down the current name of the home directory.
5. Click the home directory to select it. Click again in the name of the home directory to select it for editing.
6. Enter the new name for the home directory (remember, the home directory and the short name that you'll be changing in the next few steps must match).
7. Write down the new home directory name.
8. Launch System Preferences by clicking its Dock icon, or selecting System Preferences from the Apple menu.
9. Select the Users & Groups preference pane.
10. In the Users and Groups preference pane, click the lock icon in the bottom left corner, and then supply your administrator password (this may be the password for the spare admin account, not your normal administrator password).
11. In the Users & Groups window, right-click the user account whose short name you wish to change. From the pop-up menu, select Advanced Options.
12. Edit the Account Name field to match the new home directory name you created in the previous steps.
13. Change the Home Directory field to match the new name you created in step 6. (Hint: You can click the Choose button and navigate to the Home Directory instead of typing in the new name.)
14. Once you have made both changes (account name and home directory), you can click the OK button.
15. The new account name and home directory should now be available to you.
16. Log out of the administrator account you used to make the changes, and log back into your newly changed user account.
17. Be sure to check your home directory, and ensure that you have access to all of your data.

If you can't log in, or if you can log in but can't access your home directory, chances are the account name and home directory names you entered don't match. Log in again using the spare administrator account, and verify that the home directory name and account name are identical.

Changing the Full Name of a User Account

The full name of a user account is even easier to change, although the process is slightly different for OS X Yosemite than older versions of OS X.

The user who owns the account, or an administrator, can edit an account's Full Name.

OS X Yosemite Full Name

1. Launch System Preferences by clicking its Dock icon, or selecting System Preferences from the Apple menu.
2. Choose the Users & Groups item.
3. Click the lock icon in the lower left corner, and then supply the administrator password for the account you're currently using.
4. Right-click the user account whose full name you wish to change. From the pop-up menu, select Advanced Options.
5. Edit the name that appears in the Full Name field.
6. Click the OK button to save your changes.

OS X Mavericks and Earlier

1. Launch System Preferences, and then select the Users & Groups preference pane.
2. Select the user account you wish to change from the list.
3. Edit the Full Name field.

That's it; the full name has now been changed.

OS X has come a long way from the days when typos in account names were something you had to live with, unless you were willing to look up various Terminal commands to try to correct a silly mistake. Account management is now an easier process, one that anyone can handle.