Water-use data were compiled for the 78 municipios of the Commonwealth of Puerto Rico for 2005. Five offstream categories were considered: public-supply water withdrawals and deliveries, domestic self-supplied water use, industrial self-supplied ground-water withdrawals, crop irrigation water use, and thermoelectric power freshwater use. One water-use category also was considered: power-generation instream water use (thermoelectric-saline withdrawals and hydroelectric power). Freshwater withdrawals and deliveries for offstream use from surface- and ground-water sources in Puerto Rico were estimated at 712 million gallons per day (Mgal/d). The largest amount of freshwater withdrawn was by public-supply water facilities and was estimated at 652 Mgal/d. The public-supply domestic water use was estimated at 347 Mgal/d. Fresh surface- and ground-water withdrawals by domestic self-supplied users were estimated at 2.1 Mgal/d and the industrial self-supplied withdrawals were estimated at 9.4 Mgal/d. Withdrawals for crop irrigation purposes were estimated at 45.2 Mgal/d, or approximately 6.3 percent of all offstream freshwater withdrawals. Instream freshwater withdrawals by hydroelectric facilities were estimated at 568 Mgal/d and saline instream surface-water withdrawals for cooling purposes by thermoelectric-power facilities was estimated at 2,288 Mgal/d.