Cell service in Costa Rica | Telecom Consumer Discussion Forums

First off, if you are traveling Costa Rica, DO NOT use your US based phone there.  Roaming charges are about $4\min. 

What we did was we brought our unlocked phone from the states, and just bought a pre-paid SIM from Movistar.  The rates were pretty cheap, and in a country where internet is difficult to come by, it came in very handy when checking in with the family.  Coverage was a bit lacking, but CR is mostly undeveloped, and we were expecting that.  We did get coverage in most of the towns we visited, but not on the roads between towns.