usermod [options] LOGIN
-d, --home HOME_DIR
The user's new login directory.
If the -m option is given, the contents of the current home
directory will be moved to the new home directory, which is
created if it does not already exist.
Move the content of the user's home directory to the new location.
This option is only valid in combination with the -d (or --home)
usermod will try to adapt the ownership of the files and to copy
the modes, ACL and extended attributes, but manual changes might
be needed afterwards.
-l, --login NEW_LOGIN
The name of the user will be changed from LOGIN to NEW_LOGIN.
Nothing else is changed. In particular, the user's home directory
name should probably be changed manually to reflect the new login
So you want
sudo usermod -m -d /home/new_login_name old_login_name
sudo usermod -l new_login_name old_login_name
The first command will move your login directory; the second command will edit the relevant files that reference your name (
new_login_name. You didn't ask, but you may also want to change your group name as with
groupmod in an analogous fashion (
sudo groupmod -n new_group_name old_group_name).