The best months to visit Costa Rica are March and February. See monthly temperatures, rainfall and rain days (1991–2020 averages) to plan your trip.
Average daytime high and monthly rainfall in Costa Rica: January 22°C / 95mm; February 22°C / 66mm; March 24°C / 61mm; April 24°C / 99mm; May 24°C / 358mm; June 23°C / 381mm; July 22°C / 296mm; August 23°C / 352mm; September 23°C / 401mm; October 22°C / 431mm; November 21°C / 319mm; December 21°C / 162mm.