This study estimated the domestic water demand of a person in Bontoc, Mountain Province, Philippines. It uncovered the different household approaches on collecting and using water in the light of water scarcity. Forecasting future domestic water supply and demand leads to the determination of optimal future levels of water use and supply and hence to the design of an effective water demand management program. Frequency distribution was used to describe the data gathered; Analysis of Variance was used to test the mean differences in domestic water consumption; and multiple regression analysis was used to define the domestic water demand equation, estimate, and forecast This study found out that the two main sources of water managed by the Bontoc Water Unit discharged an average of 28 liters per second. The estimated average domestic water consumption of a resident in Bontoc, Mountain Province, Philippines is 90.09 liters per day on activities such as personal hygiene (44%), sanitary services (30%), cooking (16%), laundry (8%), and drinking (2%). Multiple regression analysis reveals that as household income increases and the household head educational attainment advances, per capita domestic water demand increases. However, as household size increases, per capita water demand decreases. From the forecasted data of domestic water supply and demand, there is an undersupply of water of 101,054 liters per day on 2016 with an annual 30% average increase.