Healthcare access and a high quality of the provided services to healthcare users are fundamental human rights according to the Alma Ata Declaration of 1978. Although 45 years have passed since then, health inequalities still exist, not only among countries but also within populations of the same country. For example, several small Greek islands have only a small Primary Healthcare Center in order to provide healthcare services to the insular population. In the current study, we investigated the level of self-reported overall, dental and mental health status and the level of satisfaction regarding the access to and the quality of the healthcare services provided by the Primary Healthcare center of Alonissos, along with registering the requirements for transportation to the mainland in order to receive such services. In this questionnaire-based cross-sectional study, 235 inhabitants of the remote Greek island of Alonissos that accounts for nearly 9% of the population participated (115 males and 120 females). The self-reported overall health status was reported to be moderate to very poor at a percentage of 31.49%, and the results were similar for dental and self-reported mental health status. Although nearly 60% of the participants reported very good/good quality of the healthcare provision, only 37.45% reported that the access to healthcare was very good/good, while around 94% had at least one visit to the mainland in order to receive proper healthcare services. Strategies for improving access to healthcare services need to be placed in remote Greek islands like Alonissos.