Developed countries throughout the world are challenged with the ageing of their labour force. In these societal contexts, low employment rates and early labour market exits of older employees are at stake, as well as arrangements for retirement, financial household considerations and mutual obligations between generations. Although proactive behaviour has been extensively studied, no research has addressed the proactive behaviour of older employees themselves when facing (re)hiring and retention versus early retirement. For the first time, this study tests the relationships of proactive behaviour with job-related affective well-being and anticipated retirement age in a sample of employees aged 50+ (N = 89) in Belgium. The findings are obtained by using a self-report questionnaire. Statistical analysis includes correlation and regression analysis. Major findings are that (i) proactive older employees feel energetic, enthusiastic, inspired, at ease, relaxed and satisfied; and (ii) later retirement is anticipated when experiencing positive affective well-being at study.