Being romantically partnered is widely seen as a societal norm, and it has been shown to be positively associated with important life outcomes, such as physical and mental health. However, the percentage of singles is steadily increasing, with more people staying single for life. We used the Survey of Health, Ageing and Retirement in Europe (SHARE; N = 77,064, mainly ≥ 50 years, 27 countries) to investigate Big Five personality traits and life satisfaction in lifelong singles compared with ever-partnered individuals. Specification-curve analyses suggested that lifelong singles were less extraverted, less conscientious, less open to experiences (dependent on singlehood definition), and less satisfied with their lives. Effects were stronger for never-partnered than for never-cohabitating or never-married individuals and were partly moderated by gender, age, country-level singlehood, and gender ratio. Our study provides insights into the characteristics of lifelong singles and has implications for understanding mental health and structures of social support in older individuals.
