Pelotas is a Brazilian city and municipality (município), the fourth most populous in the southern state of Rio Grande do Sul, after Porto Alegre, Caxias do Sul and Canoas. It is located 270 km (168 mi) from Porto Alegre, the state's capital city, and 130 km (80.8 mi) from the Uruguayan border. The Lagoa dos Patos lies to the east and the São Gonçalo Channel lies to the south, separating Pelotas from the city of Rio Grande.

Rio Grande do Sul is a state in the southern region of Brazil. It is the fifth-most populous state and the ninth-largest by area. Located in the southernmost part of the country, Rio Grande do Sul is bordered clockwise by Santa Catarina to the north and northeast, the Atlantic Ocean to the east, the Uruguayan departments of Rocha, Treinta y Tres, Cerro Largo, Rivera, and Artigas to the south and southwest, and the Argentine provinces of Corrientes and Misiones to the west and northwest. The capital and largest city is Porto Alegre. The state has the highest life expectancy in Brazil, and the crime rate is relatively low compared to the Brazilian national average. Despite the high standard of living, unemployment is still high in the state, as of 2017. The state has 5.4% of the Brazilian population and is responsible for 6.6% of the Brazilian GDP.