There are many airlines that offer flights to Costa Rica. Here are a few examples:

American Airlines: American Airlines operates flights to Costa Rica from various cities in the United States, including Miami, Dallas, and Charlotte.

Delta Air Lines: Delta Air Lines operates flights to Costa Rica from various cities in the United States, including Atlanta, New York, and Los Angeles.

United Airlines: United Airlines operates flights to Costa Rica from various cities in the United States, including Houston, Newark, and Denver.

Spirit Airlines: Spirit Airlines operates flights to Costa Rica from various cities in the United States, including Fort Lauderdale, Orlando, and Detroit.

Copa Airlines: Copa Airlines, a Panamanian airline, operates flights to Costa Rica from various cities in the United States, including Miami, New York, and Los Angeles.

These are just a few examples, and there may be other airlines that offer flights to Costa Rica as well. It is a good idea to check with a number of different airlines and compare prices to find the best deal for your trip.