Rio is an unincorporated community and census-designated place (CDP) in Martin County, Florida, United States. The population was 980 at the 2020 census.
History
Rio proper was platted as "Rio St. Lucie", but the post office established on March 24, 1893, was called "Rio San Lucie". On December 1, 1897, the post office name was shortened to "Rio". The Rio post office was discontinued on March 15, 1902, with the area being taken over by the post office at Goslingville, which was located on the narrow peninsula just north of the present-day Roosevelt Bridge. On April 6, 1904, the Rio post office was reactivated and it continued until October 15, 1927, when it was added to the post office at Jensen, now known as Jensen Beach.
Geography
Rio is located in northeastern Martin County where it sits on the north side of the St. Lucie River across from Stuart, the county seat. It is bordered to the north and east by Jensen Beach and to the northwest by part of the Stuart city limits.
According to the United States Census Bureau, the Rio CDP has a total area of , of which are land and , or 58.19%, are water.
As of the census