High Quality Content by WIKIPEDIA articles! Pasco County is a county located in the U.S. state of Florida. As of 2000, the population was 344,765. The July 1, 2007 census estimate according to the U.S. Census Bureau for the county is 462,715. Its county seat is Dade City, Florida which is in the northeast part of the county - somewhat removed from the main centers of population in the western half of the county. Duplicate county government offices and court facilities are also located in the New Port Richey area on the west side of the county. It is the 38th fastest growing county in the country with a 30.6% increase and has grown by 105,403 residents since the year 2000. Pasco, along with Hernando, Hillsborough, and Pinellas counties, comprise the Tampa-St. Petersburg-Clearwater, Florida Metropolitan Statistical Area.