The association of phonological and lexical-semantic processes with spelling ability in children has received scant research interest even though uncovering such associations can increase our understanding of literacy development. A cross-sectional study was carried out with 42 6- and 8-year-old children in the southeast of Ireland. The children took part in tasks assessing reading, letter-sound knowledge, phonological ability, phonological short-term memory, and rapid automatized naming. They also completed an assessment of spelling ability involving regular words, irregular words, and pseudowords. Analyses revealed that, for both age groups, and for all three word types, spelling accuracy was strongly associated with phonological ability scores. In contrast, phonological short-term memory was found to be significantly associated with regular word and total word spelling for the younger group. For the older group, rapid automatized naming was associated with all word categories. Qualitative analysis of the spelling errors revealed that an increase in spelling ability was accompanied by greater prevalence of phonologically appropriate errors. Our findings have important implications for teaching and assessment practices for spelling.