Emerging adults use text messaging as a principal form of social communication, day and night, and this may compromise their sleep. In this study, a hypothetical model was tested linking daytime and nighttime text message use with multiple sleep characteristics. Subjective and objective measures of texting and sleep were utilized to assess 83 college students over a seven-day period during an academic term. Greater number of daily texts, awareness of nighttime cell phone notifications, and compulsion to check nighttime notifications were significantly associated with poorer subjective sleep quality. Awareness of nighttime notifications was significantly associated with higher self-reported global sleep problems and more sleep disruptions. Results suggest potential benefits of targeting nighttime texting habits in health promotion efforts for emerging adults.