Both clubs confirm this.
Romero joined Tottenham in 2021 and was named captain for the past season. He made a total of 156 appearances for the London club, where he was teammates with Swedes Dejan Kulusevski and Lucas Bergvall.
The 28-year-old centre back was part of Argentina's World Cup squad that finished second in the summer after losing the final to Spain, a match that Romero started.
The contract with Atletico Madrid runs until 2031.
