Knowledgebase
How to add fields to the customer registration form in Magento
The admin panel of Magento has options that allow you to add more fields to the default ones on the customer registration form. If you haven't made any changes to the registration form, users only have to specify their first and last name, an email address and a password in order to create a customer account. From the admin panel you can add several other fields quickly and easily without the need for any custom code modifications.
After you log in to the admin panel go to System menu>Configuration>Customer Configuration button in the Customers section on the left>Name and Address Options panel on the right. After you click on the panel to expand it you'll see various drop-down menus each of them corresponding to a field that can be included to or excluded from the registration form. The name of the drop-down menu suggests what the field is for. By default, these drop-down menus are set to No, meaning that the field is not included on the registration form. You can set them to Optional if you want to include the field as an optional one, or you can set them to Required if you want the user to be required to type/select a value for the field in order to be able to create an account.
For example, if you set the Show Prefix drop-down menu to Optional or Required, there will be a field on the registration form for a prefix (e.g. Mr., Mrs., Ms., Dr., etc.). If you enable this option, you can use the Prefix Dropdown Options setting that's just under the Show Prefix drop-down menu to supply a list of available values that the customer will be able to choose from a drop-down menu on the frontend. Just type the values in the field for Prefix Dropdown Options and separate them with a semicolon (e.g. Mr.;Mr.;Ms.;Dr.). If you don't type anything in the field, there will be an empty text field instead of a drop-down menu on the registration form and the user can type the prefix in that field. The same principle is true for the Show Suffix and Suffix Dropdown Options settings. You can use those to include a field on the registration form for a suffix such as Sr. or Jr.
You can use the drop-down menus Show Middle Name, Show Date of Birth and Show Gender to add on the registration form options for the middle name, for the date of birth and for the gender of the customer. You can make the date of birth and the gender fields required, while the middle name can only be added as an optional field.
After you're done with the settings don't forget to click on the Save Config button.