The 25 - yr - outdated Spain international is heading to Stamford Bridge soon after the Blues fulfilled the 40 million euro (32m) purchase -out clause in his contract with Atletico.
The Premier League club declared the information on their formal web site in a small assertion.
The statement study : "Chelsea Football Club can validate an settlement has been achieved with Atletico Madrid for the transfer of Diego Costa, with Chelsea assembly the obtain -out clause for the Spanish international."
Costa has very long been joined with a move to Chelsea as manager Jose Mourinho seems to fortify his attacking possibilities for upcoming year.
In a assertion on Tuesday night time, Atletico explained Costa had sought a go to Chelsea but the club experienced insisted on obtaining his total purchase -out clause.
"Diego Costa communicated at the stop of previous time his will to be transferred to Chelsea and today the two golf equipment have reached an settlement for which the London club need to fork out the complete amount set as the obtain -out clause in the agreement amongst the player and the club," the statement said.
He spearheaded Atleticos attack in a unforgettable 2013/ fourteen campaign in which they gained La Liga and arrived at the Champions League closing underneath Argentine supervisor Diego Simeone.
Costa scored 36 aims in all competitions in advance of heading to his native Brazil for the Entire world Cup with Spain, despite the fact that he unsuccessful to make an influence as the defending champions made an early exit from the tournament.
You can be ready to view Diego Costa in Champions League motion up coming time on Sky Athletics five - the new house of European soccer.