The work role is crucial for one's identity and subjective well-being. From a role enhancement perspective, subjective well-being might increase after the transition to work and decrease after retirement. From a role strain perspective, the opposite might be true. Thus, entering and leaving working life might have benefits and costs, leading to improvements in some but impairments in other well-being indicators. To test these assumptions, we examined short-and long-term changes in life satisfaction, happiness, sadness, anxiety, and anger in the 5 years before and 5 years after the transition to work and retirement, respectively. Between 2007 and 2019, each facet of subjective well-being was repeatedly assessed in 2,720 (expectant) career starters and 2,007 (expectant) retirees from the German Socio-Economic-Panel Study. Multilevel analyses adjusted for time-dependent confounders indicated that young adults were more satisfied with their lives in (but not beyond) the first year of working life compared to before, which is in line with setpoint theory. In the first 5 years of working life, career starters became happier but also angrier, supporting both the role enhancement and the role strain perspective. Older adults became less satisfied, less happy, sadder, and more anxious in the 5 years before retirement. However, in and after the first year of retirement, they were more satisfied, happier, less anxious, and less angry than before, supporting the role strain perspective. Our findings show that working life is a double-edged sword that influences individual well-being indicators in partially opposing ways.