Zephyrhills is a city in Pasco County, Florida, United States. The population was counted at 17,194 in the 2020 census. The city is the …Zephyrhills is a city in Pasco County, Florida, United States. The population was counted at 17,194 in the 2020 census. The city is the headquarters of the Zephyrhills bottled water company. The current mayor is Melonie Monson.