I want to add a custom filed on the Billing Customer Address and i want this filed to appears on the registration page too.
Does anyone know what steps i need to follow to do this? The only thing I found is this link: http://excellencemagentoblog.com/blog/2011/11/29/magento-adding-custom-field-to-customer-address/
but this post is from 2011 and i don't know if it will work, because i use magento 18.104.22.168
Thank you in advance.