InmateAid has a service that allows inmates to write a member through the site. Some members would like to write inmates but keep their address confidential. This service works for members who would like a pen pal relationship without having to disclose where they live. The service cost $1.49 to retrieve the letter from you account.
https://www.inmateaid.com/ask-the-inmate/when-i-send-these-letters-to-my-girlfriend-on-here-will-she-be-able-to-reply-to-me-as-well#answer
Accepted Answer Date Created: March 27,2013