Cognitive, word-level reading, spelling and writing measures were administered to academically at-risk undergraduates with writing difficulties to examine their literacy profiles; and performance was compared to typically-achieving writers. The at-risk students were slower and less accurate on measures of sight word reading, lexical decision, alpha-RAN, and were less accurate in making rhyming decisions for words that varied in their visual and phonological similarity than typically-achieving writers. Students also produced misspellings that were less orthographically plausible, and made more spelling errors and used less sophisticated vocabulary in their essays, despite good oral vocabulary, than students without writing difficulties. Findings are discussed in relation to the importance of well-developed word-specific knowledge into adulthood for skilled writing, and in relation to the effectiveness of self-report in the present study as a screening tool to research adult writing difficulties. (Contains 4 tables.)