This study investigates whether work involvement moderates the negative effect of job insecurity on general well-being, and whether reduced general well-being partially explains why job insecurity is associated with increased turnover intentions. The participants were 178 members (52% female) of an online panel who provided information about job insecurity, work involvement, two measures of general well-being (affective and cognitive), and turnover intentions on 2 occasions at an interval of 6 months. In line with expectations, work involvement buffered the negative effect of job insecurity on well-being; however, the buffering effect was significant only for the cross-sectional effect of job insecurity on cognitive well-being. Furthermore, multiple mediation analysis demonstrated that well-being partially mediated the effect of job insecurity on turnover intentions; interestingly, the cross-sectional effect of job insecurity on turnover intentions was partially mediated by cognitive well-being, whereas the longitudinal effect was partially mediated by affective well-being only. The results suggest that the stress process associated with job insecurity differs, depending on which aspect of general well-being and which time frame is investigated.