Abstract Objectives Personality traits are broadly related to medical conditions, but there is limited research on the association with the risk of arthritis. This multicohort study examines the concurrent and prospective associations between personality traits and arthritis risk. Methods Participants (N > 45,000) were mostly middle-aged and older adults from 6 established longitudinal cohorts. Baseline assessments of personality traits, covariates (age, sex, education, race, ethnicity, depressive symptoms, body mass index, and smoking), and arthritis diagnosis were obtained in each sample. Arthritis incidence was assessed over 8–20 years of follow-up. Results The meta-analyses identified an association between higher neuroticism and an increased risk of concurrent (odds ratio = 1.20, 95% confidence interval [CI] = 1.16–1.24; p < .001, I2 = 40.27) and incident (hazard ratio = 1.11, 95% CI = 1.08–1.14; p < .001, I2 = 0) arthritis and between higher conscientiousness and a decreased risk of concurrent (odds ratio = 0.88, 95% CI = 0.86-0.90; p < .001, I2 = 0) and incident (hazard ratio = 0.95, 95% CI = 0.92–0.98; p = .002, I2 = 41.27) arthritis. Higher extraversion was linked to lower risk of concurrent (odds ratio = 0.92, 95% CI = 0.88–0.96; p < .001, I2 = 76.09) and incident (hazard ratio = 0.97, 95% CI = 0.95–0.99; p = .018, I2 = 0) arthritis, and openness was related to lower risk of concurrent arthritis (odds ratio = 0.96, 95% CI = 0.93–0.99; p = .006, I2 = 35.86). Agreeableness was unrelated to arthritis. These associations were partially accounted for by depressive symptoms, body mass index, and smoking. There was no consistent evidence of moderation by age or sex. Discussion Findings from 6 samples point to low neuroticism and higher conscientiousness as factors that reduce the risk of arthritis.