Heritage learners comprise a substantial proportion of second language learners, including L2 Korean learners. Previous studies have shown that the vast majority of heritage language learners display weakness in orthographic accuracy. Due to their previous extended exposure to oral discourse and limited experience in written language, heritage speakers tend to write the way they would speak, which results in frequent spelling errors. This study describes the construction and implementation of a dictation programme in a college Korean language classroom and discusses the use of dictation as a learning device to overcome orthographic errors. The online, computerised dictation programme and in-class dictation activities employed proved to be effective in sensitising heritage learners to written forms of the target language and helping them make connections between spoken sounds and written forms. Feedback provided by learners was positive and suggested that the approach had the intended effect on learning processes. (Contains 1 figure, 4 tables and 8 notes.)