This is a personal checklist, not a general Costa Rica checklist. There is no "heard only" included in this list. Every bird was actually seen in the locations mentioned. There are currently over 625 sp. in this list. For information on selected birding locations mentioned here, check the Locations page for site information, or the Maps pages for directions.
Ebird is now the most reliable way to understand bird status and distribution at specified locations around Costa Rica. The ebird website has hotspot checklists from most locations on this website, and I have included links to them on individual location pages created here. Most Costa Rican birders and bird guides use ebird regularly, and most locations have substantial data inputted into the database. You can create printable checklists for each location you visit. A link to "printable checklist" is available for each hotspot on the ebird website.