There has been little research examining clinical correlates of late-onset OCD in a large sample of individuals with a primary diagnosis of OCD. Using a sample of 293 consecutive subjects with lifetime DSM-IV OCD, we compared subjects with late-onset (after age 30 years) OCD to those with earlier onset on a variety of clinical measures. Symptom severity was examined using the Yale-Brown Obsessive Compulsive Scale. Thirty-three (11.3%) of the 293 subjects with OCD reported onset of OCD on or after age 30 years (mean age of OCD onset of 38.8+/-9.7 years). Subjects with late-onset had significantly shorter durations of illness prior to receiving treatment, less severe obsessinality, and a trend demonstrating a greater likelihood of responding to cognitive behavioral therapy (CBT). Late-onset OCD subjects were also significantly less likely to report contamination, religious, or somatic obsessions. Comorbidity, insight, depressive symptoms, quality of life, and social functioning did not differ between groups. These preliminary results suggest that although onset on or after age 30 years is fairly uncommon among people with OCD, individuals developing OCD later in life have similar clinical characteristics as those with earlier onset and may respond better to CBT.