Biodiversity follows distinct and observable patterns. Where to systems meet, biodiversity is often increased, due to overlapping occurrence ranges and the presence of specialized species that can tolerate the dynamic conditions of the transition zones. One of the most pronounced transition zones occurs at shores, where oceans and terrestrial habitat collide, forming the shore-inland transition zone. The relevance of this transition zone in shaping a system’s community structure is particularly pronounced on small islands due to their high shore-to-inland-area ratio. However, the community structure of insular faunas along this transition zone is unknown. Here, we investigated the diversity patterns along the beach-inland transition zone of small islands and tested the hypothesis that species diversity increases towards the transition zone where beach and interior habitat meet. By measuring environmental parameters, resource availability, and macrofauna diversity along transects running across the beach-inland transition zone, we show that a gradual change in species composition from beach to the inland exists, but neither taxa richness, Shannon diversity, nor overall abundance change significantly. These findings give important insight into insular community structure at the transition zone from sea to land that are relevant to better understand the dynamic and unique characteristics of insular ecosystems.