Little is known about conceptual integration processes and their contributions to memory representations that are constructed in sentence comprehension among adults with underdeveloped literacy skills. We measured word-by-word reading time to examine variation of responsiveness to demands of lexical and conceptual processing during sentence comprehension in a sample of adults with reading proficiency ranging from 4th grade through college-level. Relative to those of their more skilled counterparts, the reading times of adults with lower levels of literacy skill were more sensitive to word-level features, but showed a reduced lengthening at sentence-final words ("wrap up"), which has been argued to reflect conceptual integration processing. They also showed poorer sentence memory. However, regardless of literacy level, readers with better overall sentence memory engaged in a reading strategy marked by a larger sentence wrap-up effect. These findings suggest a pathway to intervention for struggling adult readers.