Abstract This article complements my article on “Single-Script Mixed-Code Literary Sources from the Cairo Genizah” (2018). It begins with introductory comments on the phenomenon of mixed code in Judeo-Arabic, as a continuously spoken and written Jewish language from medieval to modern times. While the documentary sources in the Cairo Genizah (a Jewish medieval archive found in the loft of the Ben Ezra Synagogue in Cairo) have drawn scholars’ attention to this phenomenon, there are few discussions of code switching in dual script Judeo-Arabic literary sources. The article presents and discusses two Genizah sources of this kind (as well as one new documentary source), which feature both Hebrew and Arabic scripts in the space of the same fragment. It argues that the haphazard appearance of code switching in such fragments is misleading. The analysis shows there are specific conditions that govern the mixing of Hebrew and Arabic scripts, and highlights its sociolinguistic background. Code switching is a dominant feature of single script Judeo-Arabic literary sources as well, meaning, those penned solely in Hebrew or Arabic script, which lie beyond the scope of the present study. A systematic survey and study of the Genizah literary sources relevant to both categories (single and dual scripts) is therefore a desideratum, and is bound to lead to a better understanding of the sociolinguistic functions of mixed code in Judeo-Arabic writings and culture.