The former Tottenham manager had already verbally agreed to take over from Frank Lampard at Stamford Bridge, and now he has put pen to paper to make the deal official.
It’s believed he has signed a three-year deal after flying to England from Spain to complete the formalities for his new job.
The 51-year-old Argentine has been out of managerial work since being sacked by Paris Saint-Germain at the end of last season.
Pochettino agreed to take over the side in April, but was to join in the summer with Lampard seeing out the season despite the Blues’ poor form.
It is understood the 51-year-old will seek talks with Lampard before he formally takes on the role at the end of the season, though the managerial duo are yet to have held any planning discussions.
Previous conversations between Pochettino and the Chelsea executives were described as ‘incredibly positive’ after he became front-runner for the job when Julian Nagelsmann backed out.
Chelsea have had a disastrous campaign, finishing in the bottom half of the Premier League in a season to forget.
They have had four at least interim managers, though will hope for a more settled future with Pochettino taking the reigns next term.
As reported by Mail Sport earlier last week, Pochettino would ideally like to sign a new goalkeeper, central midfielder and striker.