Unhappily Single? Towards an Accurately Estimated Association Between Romantic Relationship Status and Life Satisfaction

Being in a romantic relationship is associated with better mental health and well-being, with partnered individuals often reporting higher life satisfaction (LS) than singles (weighted Cohen’s d = 0.38). However, most prior studies have suffered from small sample sizes, confounding variables, and single-method bias. To simultaneously address these limitations, we used the large Estonian Biobank (N = 77,378) and combined self- and informant-reports to accurately estimate the association (dₜᵣᵤₑ) between romantic relationship status and life satisfaction. We examined potential moderators (age, gender, income, parental status), confounders (personality traits, genetic influences, single-method biases), and mediators (satisfaction with financial situation and residence). Individuals in romantic relationships had significantly higher life satisfaction than singles (β = .34). Controlling for personality traits reduced the effect size from β = .34 to .23. In a sibling discordant analysis controlling for a) shared familial backgrounds, b) polygenic scores for life satisfaction and c) personality traits, the effect was similar, β = .24. However, after combining self-report and informant report to reduce measurement error and controlling for personality nuances, the within-family association was dₜᵣᵤₑ = .33. This represents the most bias-free estimate yet of how strongly romantic relationship status relates to life satisfaction and suggests that previous studies had both over- and underestimated the link, due to confounders and measurement issues, respectively. The single-partnered difference was larger among men and those without children, and it was partially mediated by satisfaction with financial situation and residence.