The 23-year-old Netherlands international defender had been linked with moves to Fulham, Queens Park Rangers and Southampton.
"This is really a dream come true," he told Dutch television station Omroep Gelderland.
"It was all arranged very quickly and of course I am very delighted. Happily everything is coming to an end."
Buttner signed his first professional contract with Vitesse in 2008 following a three-year spell in their youth team.