This paper estimates the effects of risky behaviors (e.g., smoking, alcohol, marijuana, risky sex) on subjective well‐being. To identify these effects from endogenous sorting, I use information from the 1997 National Longitudinal Survey of Youth and a system of simultaneous equations for participation in four risky activities and formation of individual happiness. My results provide evidence that smoking and alcohol decrease subjective well‐being by 2.5% and 2.4%, respectively. By contrast, the relationship between having sex with multiple partners, although positive, is not statistically significant at conventional levels. Nevertheless, these effects dwindle over time until participation in any of these behaviors does not have a long‐run impact on well‐being, with the exception of smoking and alcohol consumption, which have a persistent negative impact on subjective well‐being. The results highlight the importance of controlling for endogeneity of risky behaviors and provide an explanation as to why most individuals who engage in such behaviors do not develop longer‐lasting addictions.