Katy is a city located in the U.S. state of Texas within the Houston-Sugar Land-Baytown metropolitan area. The city is located partially in the counties of Fort Bend, Waller, and Harris. As of the 2000 U.S. Census, Katy's population was 11,775. Katy apartments for rent comparison page shows most up to date rent information on Katy apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.