• Multimodal integration model for Public Transport Service (PTS) in an island scenario • Mobility-based spatial interpretation for the benefit of the population • Use of real data obtained by the Kriging method • Transport modes do not reflect the socio-physical and economic reality of the island The purpose of this paper is to highlight the critical aspects of islands context transportation accessibility by suggesting a more innovative, safer, and more sustainable framework for public transport service (PTS) and place-based organisation, as well as by integrating the latest tendencies in mobility. Specifically, this research focuses on multimodal integration models for PTS that consider the existing infrastructure system and the socioeconomic issues typical of an island environment. This topic has received inadequate consideration in the scientific literature on islands. To achieve these aims, an analytical-numerical approach is adopted. Starting from initial origin-destination matrices (O/D) surveyed by the National Institute of Statistics (ISTAT), a methodology was implemented to compute the geographical distribution of trips, and thereafter, the values distributed over the whole region were interpolated by Surfer software with the Kriging method. This methodology was applied to the Sardinia case study particularly emblematic because it has seen a tremendous transition over the previous decades, resulting in a massive socio-economic gap between inland and coastal areas, that led to an increase in private vehicles for transportation purposes, primarily for business and pleasure. The application, replicable in other islands that have highlighted the same socio-economic problems linked to poor mobility planning, shows an accessible spatial planning approach, combining PTS and rental for driver services, by considering the principles and issues of island contexts. This research gives an important scientific contribution by emphasising the quality of transport infrastructures, place-based organisation, population distribution, and physical configuration of the Insular Region, as well as by considering the most pressing issues of island contexts. Findings could help island governments in revising their policy and practice of transport, accordingly.