In the present study we examined the relation between alphabet knowledge fluency (letter names and sounds) and letter writing automaticity, and unique relations of letter writing automaticity and semantic knowledge (i.e., vocabulary) to word reading and spelling over and above code-related skills such as phonological awareness and alphabet knowledge. These questions were addressed using data from 242 English-speaking kindergartners and employing structural equation modeling. Results showed letter writing automaticity was moderately related to and a separate construct from alphabet knowledge fluency, and marginally (p = 0.06) related to spelling after accounting for phonological awareness, alphabet knowledge fluency, and vocabulary. Furthermore, vocabulary was positively and uniquely related to word reading and spelling after accounting for phonological awareness, alphabet knowledge fluency, and letter writing automaticity. [This is the online version of an article published in "Reading and Writing." For the final version of this article, see EJ1038942.]