OBJECTIVES: The purpose of this study was to describe the impact of RLS on overall health status, sleep, psychological functioning, work productivity, and other daily activities. METHODS: A Web-based survey was presented to a multimillion member panel of US adults. To be eligible, participants had to be at least 18 years of age and currently experiencing RLS symptoms as determined using established diagnostic criteria. In addition to gathering information related to diagnosis, treatment, and symptom frequency and severity, validated instruments were administered to assess overall health (SF-12v2), sleep (MOS Sleep), psychological distress (CES-D), and work productivity/activity limitations (WPAI and WLQ). Where possible, scores for these instruments were compared to published norms. A series of ANCOVA models were developed to evaluate the relationship between symptom severity, diagnosis status, age and gender, and the impact of RLS. RESULTS: Participants included 702 adults with RLS (396 diagnosed and 306 never diagnosed). Means for the SF-12v2 scores (PCS=35.6, MCS=42.6) were at least 1 standard deviation lower than gender- and age-adjusted general population norms. Participants reported poorer sleep quality scores across each MOS Sleep domain, with differences from published norms of more than 16 points on 100-point scales, as well as approximately one hour less sleep per night on average. A majority (64%) of the RLS sample met the cut-off score for depression on the CES-D. Compared to population norms, the RLS sample reported greater limitations in time management, physical demands, mental/interpersonal demands, general work output, and usual activities. Symptom intensity and frequency were shown to be the primary predictors of RLS impact on the various outcomes. CONCLUSION: RLS has a substantial impact on various aspects of patients' lives including HRQOL, sleep, psychological distress, and work productivity.