All USC buildings and departments have their own mail codes with which you can address inter-campus mail. You can find the different mail codes by looking up a building by its 3 letter building code on the list bellow.

Download the Campus Mail Codes: Last updated: (10/2008)
This file contains both UPC and HSC mail codes.
Campus Mail Codes.pdf

Download the Campus Building List
This file contains both UPC and HSC Buildings.
Campus Buildings Address.pdf