The enigmatic Italy international flew into Milan's Malpensa airport prior to undergoing a medical after the two clubs agreed a fee for the 22-year-old on Tuesday.
Balotelli, who moved to the Premier League from Inter Milan in August 2010, is expected to put pen-to-paper on a four-and-a-half-year contract before Thursday's transfer deadline.
The striker has endured a miserable time with City this season, scoring just one Premier League goal, and with his last start coming in the 3-2 derby defeat by Manchester United on 9 December, when he was hauled off after 52 minutes by a clearly frustrated Roberto Mancini.
Balotelli is confident he will rediscover his best form away from the Etihad Stadium and is hoping that he will receive nothing but the full backing of the Milan supporters.
Speaking to the Milan Channel, he admitted: "I ran to Milan.
"I had wanted to play here for a long time. The start of this season was negative, but with this jersey I will do better.
"I made some important choices, so I hope they can bring good luck to me and the team. I just want the fans to love me."
Milan vice-president Adriano Galliani has admitted the transfer is a 'dream come true' and believes the arrival of Balotelli can only drive the Italian giants on to greater heights.
Galliani told the club's official website: "It is a dream come true and something that we all wanted, with the president Silvio Berlusconi at the forefront.
"With the arrival of Mario, we have strengthened our team a lot.
"We have worked so hard and Mario has been in our hearts for a long time and finally we have succeeded in signing him."