Mercedes is a city in Hidalgo County, Texas, United States. The population was 15,570 at the 2010 census and grew to an estimated 15,401 in 2009. It is part of the McAllen–Edinburg–Mission Metropolitan Statistical Area.
Mercedes is located at 26°8′58″N 97°55′7″W / 26.14944°N 97.91861°W / 26.14944; -97.91861 (26.149315, -97.918675).
According to the United States Census Bureau, the city has a total area of 8.6 square miles (22.4 km²), of which, 8.6 square miles (22.2 km²) of it is land and 0.1 square miles (0.2 km²) of it (0.69%) is water.