Over the last decade, several flood early warning systems have been established in Nepal, helping reduce the number of people affected and killed by floods. However, there are still challenges in communicating flood warning to the most vulnerable. The unavailability of real-time monitoring in smaller streams and tributaries has created challenges for communicating early warning. The ongoing restructuring process of the multilevel governance system in the country also presents challenges, specifically institutional such as insufficient coordination among relevant agencies, lack of adequate personnel, limited budget, and unclear roles and responsibilities. This study uses the Alexander framework (2015) to identify gaps in flood early warning communication in relation to their technical, institutional and socio-cultural components. Qualitative research methods in the form of key informant interviews and on-site focus group discussions were conducted at the national, district and local levels to collect data, taking Ratu watershed as a case study. Based on our analysis, we conclude that, first, while progress has been made in the monitoring and forecasting of floods, integration of socio-cultural aspects that can make early warning information accessible to the most vulnerable has to be strengthened. Second, warning messages need to be co-designed with communities and tailored to meet their diverse needs for proper dissemination and timely protective action. Finally, for flood risk communication to bridge ‘the last mile’ in terms of reaching the most vulnerable in the community must take account of their distinct social, economic and political experiences in both content and delivery of the information.