In the 1950s, nuclear power generation became important and many facilities were built. Today, because of political, technical or economic reasons many reactors are being or will be decommissioned. This highly impacts energy policy regarding future energy supply and the handling of decommissioning, including dismantling capacities, regulatory control, equipment, expertise, funding or final nuclear disposal sites. This study provides a desk-based research and a scenario analysis of the present and future situation of 540 nuclear power reactors in 18 countries worldwide until 2047. For that purpose, IAEA PRIS database is extended on reactor-level by information on future usage, political decisions, preferred decommissioning strategies and the durations of the post-operational and dismantling phase. The projected market potential will continuously unfold after 2019 until mid-2030s to a stable, annual market volume of 75-85 GW, in dismantling. In the next decade, main dismantling markets are USA, Japan and Germany with a capacity reduction of 131.5 GW(e) until 2047. Germany and USA offer a stable market potential. In Japan and France, the political decisions on pending reactors and prolongations of operation times strongly influence nuclear retirements. Ukraine, Spain, Sweden and Canada are interesting smaller markets in the next years.