This study assesses chronic pain prevalence among sexual minority U.S. adults who self-identify as gay/lesbian, bisexual, or “something else,” and examines the role of select covariates in the observed patterns. Analyses are based on 2013 to 2018 waves of the National Health Interview Survey, a leading cross-sectional survey representative of the U.S. population. General chronic pain and chronic pain in 3+ sites among adults aged 18 to 64 years (N = 134,266 and 95,675, respectively) are analyzed using robust Poisson regression and nonlinear decomposition; covariates include demographic, socioeconomic, healthcare, and psychological distress measures. We find large disparities for both pain outcomes. Americans who self-identify as bisexual or “something else” have the highest general chronic pain prevalence (23.7% and 27.0%, respectively), compared with 21.7% among gay/lesbian and 17.2% straight adults. For pain in 3+ sites, disparities are even larger: Age-adjusted prevalence is over twice as high among adults who self-identify as bisexual or “something else” and 50% higher among gay/lesbian, compared with straight adults. Psychological distress is the most salient correlate of the disparities, whereas socioeconomic status and healthcare variables explain only a modest proportion. Findings thus indicate that even in an era of meaningful social and political advances, sexual minority American adults have significantly more chronic pain than their straight counterparts. We call for data collection efforts to include information on perceived discrimination, prejudice, and stigma as potential key upstream factors that drive pain disparities among members of these minoritized groups.