Costa Rica had won just two of their past nine games before Sunday but they were far too good for Northern Ireland, who made history by fielding two sets of brothers when second-half substitutes Ryan and Conor McLaughlin joined Jonny and Corry Evans.
Johan Venegas Ulloa opened the scoring for the home side on the half-hour mark when he took advantage of poor defending from a corner to head home from close range.
Campbell doubled their lead seconds after the restart and then Francisco Calvo got a third, also via a corner kick, after 66 minutes.
Costa Rica, who reached the World Cup quarter-finals four years ago before losing to the Netherlands on penalties, will face Brazil, Serbia and Switzerland in Group E this time around.
They face Belgium in Brussels in their final warm-up match on June 11.
(Writing by Andrew Downie, editing by Neil Robinson)
