Socioeconomic and climatological data of the major cities of the western region of Saudi Arabia have been used to develop several models to estimate the residential water usage for different kinds of houses. The developed models correlate the residential water usages with temperature, income, family size, price of water, and availability of a garden within the house. The study shows that the residential water uses in houses supplied by a public pipe network are 1.4–2 times greater than the residential water uses in houses supplied by tankers. It also shows that the price elasticities are very similar to those estimated in the United States. Income elasticities, on the other hand, are lower than those typically found in more industrialized countries.