Water and energy are both important resources that are inextricably and reciprocally linked. Indeed, energy production requires a lot of water (e.g., cooling water at power plants), and numerous studies have investigated the water footprint of energy production (WFEP). However, energy is typically supplied to domestic consumers by both domestic and foreign producers, so it is necessary to take both internal and external energy productions into account. The aim of this study is to evaluate the water footprints of energy production and supply in Thailand by applying standard water footprint analysis methods based on bottom-up approaches, which define separate footprints based on production and consumption perspectives. Our findings show that the WFEP for 2010 was nine times greater than that for 1986, while the water footprint of energy supply (WFES) was eight times greater because of the use of biomass energy. We discuss external dependency, the impacts on domestic water resources, and policy implications, and we suggest ways to promote a reliable energy supply by limiting the use of water resources for energy production in Thailand. (C) 2014 Elsevier Ltd. All rights reserved.