Letter knowledge and word identification are key skills for reading and spelling. Letter knowledge facilitates the application of sublexical letter-sound mappings to decode words. With reading experience, word identification becomes a key lexical skill to support decoding. In transparent orthographies, however, letter knowledge might be an enduring predictor of decoding and spelling, even in children with some reading experience. This study investigated the association of children's sublexical (letter knowledge) and lexical skills (word identification and vocabulary) with word decoding and spelling accuracy in Spanish, which is a transparent orthography. The sample consisted of 117 Spanish-speaking children, aged 8 to 10. Results revealed that (1) letter knowledge and word identification were independently associated with children's word spelling; (2) word identification was uniquely associated with word decoding; and (3) children's vocabulary level was associated with word identification. The implications of these findings were examined within the framework of reading models and the characteristics of a transparent orthography.