Climate change is considered one of the major threats to global biodiversity, as it can modify both species distributions and ecological interactions, including host–parasite relationships. This study investigates how future climatic conditions may affect the geographic ranges and niche overlap of the kleptoparasitic spider Argyrodes argyrodes and its hosts, Argiope lobata and Cyrtophora citricola, across Europe. Species occurrence data obtained from GBIF (Global Biodiversity Information Facility) were used to perform species distribution modelling and to evaluate niche overlap between the kleptoparasite and its hosts under current and future climate conditions. Future projections were developed using the IPCC Shared Socioeconomic Pathways, specifically SSP1-2.6, representing a global sustainability-oriented scenario, and SSP5-8.5,  a scenario with high greenhouse gas emissions. Two future periods were considered: 2021–2040 and 2061–2080. Current distribution models indicate that the main area of overlap between A. argyrodes and its hosts is located within the Mediterranean Basin. Under future climate scenarios, niche overlap is predicted to decline, with the strongest reduction occurring between A. argyrodes and C. citricola under the SSP5-8.5 scenario during 2061–2080. In addition, all three species are expected to undergo a northward shift in their potential distribution ranges, while areas of overlap are projected to restrict and become concentrated along the Atlantic and Black Sea coasts. These changes are likely to increase the extent of regions where the kleptoparasitic spider may occur without the presence of its hosts. Such a mismatch could result in local extinction of the parasite, a shift toward alternative host species, or the development of a more independent lifestyle based on capturing prey with its own web. Overall, we showed how climate change may substantially alter host–parasite interactions in understudied taxa and highlights the importance of including a broader range of organisms in biodiversity research to reduce taxonomic bias.