This presentation describes the results of two ongoing studies intended to gauge writing proficiency development of heritage language learners (HLLs) who are enrolled in college-level courses. A common objective for college-level heritage language curricula is the development of literacy—the domain in which HLLs generally have limited exposure due to their educational experiences. Previous research has described both oral and writing proficiency profiles of HLLs at Intermediate and Advanced levels of proficiency (Swender et al., 2014; Gatti & O’Neill, 2017; 2018; Gatti & Graves, in preparation), contributing valuable information to our knowledge of how to support proficiency and literacy development so that learners can fully engage with academic and professional communities using their heritage language. One missing piece of information, however, is an understanding of the expected pace of development, which is crucial for establishing realistic educational goals for both learners and instructors, along with how/whether this pace is related to the starting writing proficiency level of the student. Furthermore, a second missing piece of information is an understanding of how targeted pedagogical approaches to literacy might impact proficiency development—also needed for optimizing instructional impact. The two studies in this presentation intend to fill this gap in available information. They were conducted on over 180 Spanish HLLs who were enrolled in courses at two universities within the City University of New York (CUNY). Using a tool modeled after the Writing Proficiency Test developed by the American Council for the Teaching of Foreign Languages (ACTFL), as well as a literacy-based pedagogical model, these research projects intend to answer the following questions: (i) how long does it typically take for HLLs to move from one proficiency level to the next once they receive formal instruction? and (ii) do different pedagogical approaches have an impact on the speed of proficiency development?