Former Costa Rica striker Wanchope, 38, was handed control of his country when Jorge Luis Pinto stepped down in the wake of a successful 2014 World Cup campaign.
Pinto exceeded all expectations by leading Costa Rica, who had been grouped with Uruguay, Italy and England, to the quarter-finals in Brazil.
However, he was subsequently unable to reach an agreement over a new contract and Wanchope has since overseen six unbeaten matches at the helm, and victory in last year's Copa Centroamericana.
His permanent appointment was announced in a tweet by the official Fedefutbol account, which read: "The Executive Committee of the Costa Rican Soccer Federation has appointed Paulo Wanchope as new coach.
"Paulo Wanchope will be presented on Tuesday at a press conference."
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