The 21-year-old Lille playmaker, who had long been linked with a move to the Barclays Premier League, revealed he had chosen the newly-crowned European champions on his official Twitter account.
He wrote: "I'm signing for the champion's league winner."
Hazard earlier continued to keep fans of several clubs in suspense by posting he had "made up his mind" who he was going to join but declined to name the team in question.
There was no official confirmation this evening from either Chelsea or Lille that a deal had been reached over the signing of Hazard, who has been rated at £32million.
But reports in France suggest the Belgium star has agreed a five-year contract worth as much as £100,000 a week after tax.
Hazard has become one of the most sought-after players in the game this season and has actively flirted with a host of European giants.
Manchester United and Manchester City looked to be favourites for his signature until Chelsea's surprise European Cup triumph last weekend.
Hazard admitted that was a game changer and it was telling he used the expression 'Champions League winners' to describe the Blues this evening.
Chelsea would not even had been in the competition next season had they not stunned Bayern Munich last weekend.
The Blues may also have been more attractive both from a playing and financial perspective, amid suggestions City could not guarantee first-team football and baulked at Hazard's wage demands.
The Belgium star, who could line up against England in Saturday's friendly at Wembley, enjoyed a stellar season as Lille finished third in Ligue 1.
He struck a hat-trick in what was almost certainly his final game for the French outfit last weekend.
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He had already confirmed his preferred destination was England, recently telling Belgian news website HLN: "It will anyway be Manchester City, Manchester United or Chelsea.
"The decision will depend on the amount of play I would see and the position where I would play.
"Not everyone can say that he can make a choice between the three top clubs."
When asked about a possible move to Chelsea, Hazard was quoted as saying by France Football: "Now, yes. They won the Champions League so they will be back in that competition next season.
"It's important for me to play in that competition. Chelsea are a great team, with great players."
Hazard's agent John Bico recently claimed an agreement on personal terms had been reached with all parties interested in his client.
Chelsea's summer business is unlikely to end there, amid reports Porto striker Hulk is being lined up as a replacement for Didier Drogba, who quit Stamford Bridge last week following his own Champions League heroics.
Marko Marin has already signed from Werder Bremen, while Salomon Kalou and Jose Bosingwa are set to join Drogba out of the exit door.
All this with Chelsea still to appoint a permanent manager, with Gus Poyet having become the latest former player to urge them to give the job to ex-team-mate and caretaker boss Roberto Di Matteo.