"This year I was not able to win, but I had notable consistency," said Viganò. "I lacked a win, but I will correct that soon and repay the faith of my new team."
Viganò, 25, had several top 10 placings racing for Fuji-Servetto this year. He placed fourth in both Giro d'Italia's stage seven and in the Vuelta a España's stage six.
He turned professional in 2005 and joined Belgium's Quick Step team mid-season.
The new Sky team of David Brailsford has already confirmed Thomas Lövkvist, Simon Gerrans, Juan Antonio Flecha, Edvald Boasson Hagen. Viganò becomes the team's second Italian rider after Morris Possoni.
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