This article examines the role of transnational literacy practices in the biliteracy development of Mexican-American teachers who grew up on both sides of the US-Mexico borderlands. Through an analysis of literacy narratives and language history maps of bilingual education pre-service teachers, the pre-service teachers recall their memories as transnational immigrant children and the ways in which their unofficial schooling experiences shaped their development of biliteracy outside of school. As most of the case study participants had little or no access to bilingual education beyond the assimilation model, these return trips back and forth afforded them opportunities to maintain their Spanish biliteracy and bicultural identities. These teachers lived in transnational spaces and recall the ways in which growing up on the border shaped their bilingual and biliteracy development. (Contains 1 table, 3 figures and 2 notes.)