| Cheap Flights: Austin to/from San Jose, Costa Rica $189-$214 r/t [September] â Spirit Spirit has round-trip flights from Austin (AUS) to San Jose, Costa Rica (SJO) for $189-$214 with a connection. Flights in September. Departures on Monday and Thursday. Extended weekends available. Origin/Destination reversible. Note: Spirit fares do not include a free carry-on bag. Only a small personal item, like a Jansport City Scout backpack is free. You can avoid paying for seat selection if you accept the randomly assigned seat prior to boarding. Note: Spirit seats only have 28-inches of pitch; 2-to-3 inches less space than most other airlines. Click for more details and booking links Cheap Flights: Austin to/from San Jose, Costa Rica $189-$214 r/t [September] â Spirit . | 