Understanding species distributions is key to biodiversity conservation, particularly on islands where ecological communities may be vulnerable to anthropogenic pressures. The Leisler’s bat Nyctalus leisleri is a widespread European bat known for long-distance migrations, whose occurrence in the central Mediterranean remains poorly documented. Here we present the first confirmed records of N. leisleri from the Maltese Islands, based on passive acoustic monitoring conducted between April and December 2024. Acoustic recorders were deployed across Malta, Gozo, and Comino using fixed recording stations and mobile transects, with automatic call classification followed by manual validation. A total of 528 nyctaloid bat passes were recorded, of which 124 were assigned to N. leisleri based on a quantitative assessment of echolocation calls. The species was detected across both main islands, showing widespread occurrence and a seasonal activity peak in summer, consistent with patterns observed in other resident high-flying bats. These findings expand the known bat fauna of the archipelago and suggest that N. leisleri has likely been overlooked rather than absent, highlighting the importance of long-term acoustic monitoring for detecting elusive species. The continuous seasonal presence and spatial distribution we found suggest that the species may be present year-round in Malta, yet roosts, reproduction or hibernation still await concrete evidence. Our results contribute to the understanding of Mediterranean bat biogeography and emphasize the need to incorporate migratory species into conservation planning on islands. Further research should investigate roost availability, habitat use, and seasonal dynamics to clarify the ecological role and conservation status of N. leisleri in the Maltese Archipelago.