The 26-year-old joined the Florence-based club in 2012, after initially moving on a loan-deal from Udinese, who owned a portion of the player.
And after the club revealed the news on their official website on Thursday, Cuadrado – who is currently on World Cup duty with his national side Colombia – expressed his delight at being fully owned by the Viola.
“At this time I am concentrated on the World Cup and I hope to get the most with my national team,” he said.
“But, I am very happy and it is a source of pride for me to be fully owned by Fiorentina.”
Cuadrado’s impressive performances for Vincenzo Montella's side last term helped the club secure a fourth-place finish in Serie A, which has resulted in interest from several bigger European sides.
Barcelona are one of the teams rumoured to be keen on luring Cuadrado away from Italy, but Fiorentina president Andrea Della Valle recently dismissed the reports before admitting his relief at securing the player completely.
“Our goal was to be able to own 100 per cent of Juan and we have succeeded,” he told reporters.