san juan. $74 per passenger. departing tue, oct 29, returning tue, oct 29. round-trip flight with frontier airlines. outbound direct flight with frontier airlines departing from miami international on tue, oct 29, arriving in san juan luis munoz marin. inbound direct flight with frontier airlines departing from san juan luis munoz marin on tue, oct 29, arriving in miami international. price includes taxes and charges. from $74, select.