Verbal and nonverbal predictors of spelling performance in Grades 1-12 were investigated using the national norming data from a standardized spelling test. Verbal variables included number of letters, phonemes, syllables, digraphs, blends, silent markers, r-controlled vowels, and the proportion of grapheme-phoneme correspondence. The nonverbal variable was word concreteness. Word frequency was also included. Results showed that only three variables were consistently strong predictors of spelling performance: proportion of grapheme-phoneme correspondence, number of syllables, and word concreteness. Results are theoretically interpreted in terms of Dual Coding Theory and stages of spelling development. Instructional implications include increased attention to word concreteness in teaching and testing spelling.