What should my FTP settings be for an addon domain?
Once you have set up your addon domain and created an FTP user through your account's cPanel, enter the settings listed below to connect.
Host: youraddondomain.com
Username: user@yourprimarydomain.com
Password: password you created for the user
Directory: / or blank
You can always use the main FTP account and publish to the addon domain's subfolder under public_html instead.