The Mentawai Islands are located in one of the most seismically active regions in Indonesia and consistently among the top tsunami and earthquake threat locations. Therefore, preparedness is one of the vital aspects of disaster risk reduction. This study, hence, assessed the level of preparedness of local communities from the Mentawai Islands in terms of awareness, knowledge, resources, and coping mechanisms. A mixed-method design using surveys, interviews, and on-the-ground observations in rural communities to measure community preparedness and variables that impede or facilitate the ability to respond to emergencies. Island variation was marked by differences in preparedness levels. While many islanders are cognizant of the earthquake and tsunami hazards, practical preparedness—comprising early warning systems and evacuation planning, and disaster education—is missing. It underlines the need for effective partnership at the local level between the government and other stakeholders including non-governmental organizations to support and consolidate community-based disaster risk reduction initiatives. The recommendations include scaling up public awareness programs, improving access to early warning systems, and financing sturdy infrastructure that is sensitive to the specific physical and cultural setting of the Mentawai Islands. In one of the most disaster-prone areas in Indonesia, this study calls attention to the utmost urgency of coordinated action to empower, support, and build the resilience of vulnerable communities as well as to reduce the incidence of disasters.