The Ecuadorian international is coming off a solid rookie season after Toronto drafted him with the 49th overall selection.
“We are very happy to get this deal completed and keep Plata at our club,” said Toronto FC head coach Aron Winter. “Plata had a great year with us in 2011. He made a strong contribution on the pitch."
Plata, 19, completed his first season in Major League Soccer and Toronto FC after being selected 49th overall in the 2011 MLS SuperDraft. He finished the regular season with 26 appearances adding three goals and five assists.
“Re-signing Plata was a high priority for our club during the offseason," Winter said. "I have to compliment everyone involved for making this a reality. Plata wanted to remain in Toronto and we wanted to keep him. We know our fans will be happy with this announcement.”
Plata has earned one international cap for his native Ecuador.