The veteran midfielder will swap the Sounders for the Rapids as the last-place team in the Western Conference continues to re-tool.
Guatemala international Marco Pappa will have a new MLS home in 2016.
The 28-year-old midfielder was dealt to the Colorado Rapids from the Seattle Sounders for general allocation money, the teams announced Tuesday.
“We are delighted to acquire a player of the caliber of Marco,” said Paul Bravo, Rapids VP of soccer of operations and technical director told the club’s official website. “The departure of Vicente Sanchez left a gap for a chief creator and we believe Marco can step in to that vital role.