OBJECTIVE: Pain in persons at the end of life has not yet been well described. The purpose of this study is to describe the occurrence of severe pain among persons who received hospice care in the US. METHODS: Data for this study were derived from a database developed by excelleRx Incorporated, which provides pharmacy services to US hospices. The excelleRx database includes demographic and clinical data for persons during the period from February 1, 2000 - July 26, 2004. Worst pain intensity during the previous 24 hours is assessed using a zero – ten numeric rating scale (NRS; zero=none, ten=worst) by hospice nurses periodically during a person's hospice admission. RESULTS: Of 326,737 persons who received hospice care in 419 US hospices during the study period, severe pain (NRS seven – ten) was reported at least once by 20.3% of persons with at least one pain score. Of these individuals, mean age of persons who died during hospice care was 68.9 years (median 70.7, SD 14.4), median length of service was 42.0 days, 53.7% were female, 78.0% were Caucasian, 7.4% were cared for in LTC hospices, and 73.9% had a primary diagnosis of cancer. Within the subset of persons who reported severe pain and were treated in a long-term-care hospice, 66.8% were female, 78.1% were Caucasian, and 47.6% had a primary diagnosis of cancer. CONCLUSION: Severe pain was reported at least once by a substantial percentage of persons in this cohort, of those individuals cared for in long-term-care facilities, and of persons with a primary diagnosis of cancer. These data provide insight into improving the care of persons at the end of life.