what county is oldsmar, fl in
Oldsmar, Florida Oldsmar, Florida. Oldsmar is a city of 13,591, as of the 2010 census, in Pinellas County, Florida, United States.[5] The Oldsmar name dates to April 12, 1916 when automobile pioneer Ransom E. Olds purchased 37,541 acres (151.92 km2) of land by the northern part of Tampa Bay to establish R. E. Olds-on-the-Bay.