The goal of the present research is to evaluate the mediating role of job performance and its spillover of life satisfaction, a component of nonwork psychological well-being, onto psychological well-being at work. A two-wave study of 436 Canadian workers was conducted. They answered a self-reported questionnaire twice, at an interval of seven and a half months. Analyses support that contextual performance mediates the relationship between life satisfaction and psychological well-being at work. Results enrich work-non-work interface theories by demonstrating that psychological well-being can spill over through contextual performance at work.