Purpose – This paper aims to contribute to the understanding of group level differences in job satisfaction. Specifically, the authors seek to understand the shared variance in job satisfaction at the group level of jobs within organisations, in a particular industrial sector. To explain differences in job satisfaction between groups, the authors examine the role of job characteristics, particularly as these are defined within the job‐demand‐control‐support model. Design/methodology/approach – The paper presents the results of a cross‐sectional self‐report questionnaire study of 2,733 Belgian bank employees working in six specific jobs and four specific organisations. Research hypotheses are tested using multilevel analyses. Findings – There are substantial and reliable between‐group differences in job satisfaction within the banking sector. These effects are partially explained by job characteristics from the JDCS model at the individual level. At the aggregated level, only decision authority is statistically significant. Research limitations/implications – The research is limited to Belgium and to the banking sector. The general research question and findings are nevertheless relevant to other single‐sector studies in Western European countries. Practical implications – Decision authority is more important for group level job satisfaction than job demands and social support from colleagues and supervisors. Human resources managers are therefore recommended to focus more on structural differences and organisational choices that may affect job design and work systems. Originality/value – The paper aims to make a contribution to the understanding of group level job satisfaction differences in the context of sector studies.