When traveling to any country your most important concerns are staying safe and healthy during your visit. When visiting Costa Rica because you are in the tropics in a humid climate one one of the most important ways to stay healthy is being hydrated. This means drink a lot of water.
Having owned an ecolodge in Costa Rica for the last 10 years, one thing I know the Costa Rican’s take pride in, is their water. We have our water tested regularly and we have never tested anything less than 100% pure and drinkable water. The answer to if Costa Rica tap water is potable is YES! With this said there will be some small pockets of Costa Rica where it might be advised to drink bottled water. This can be due to extreme rural conditions where water taken from a source in livestock areas. You can be assured any public operating commercial area will not have this issue.
There is also bottled water sold throughout Costa Rica, but due to the purity of the water it is not uncommon for stores to simply bottle tap water and re-sell it in recycled bottles.