Cachoeirinha is a municipality located in the Brazilian state of Tocantins. It is one of the state's smaller municipalities by population, with an estimated 2,284 residents as of 2020.
The municipality covers an area of 352 square kilometres. It is situated in the northern region of Brazil, within Tocantins, a state in the country's interior that was carved out of Goiás and became a separate state in 1988.