Costa Rica: entry and exit requirements

A valid passport is required to enter Costa Rica. At the discretion of Costa Rican authorities, travelers are routinely admitted with a certified copy of their U.S. birth certificate and a valid photo identification.

The requirements to enter Costa Rica depend on your country of nationality. Generally, citizens of the United States, Canada and European Union countries do not require a visa to enter Costa Rica. With their passport, they can enter Costa Rica and remain in the country for up to a maximum of 90 days. Here is the full list of countries and the corresponding Visa requirements: Costa Rica Visa Requirement List

Depending on your nationality, you may or may not be required to apply for a visa prior to entering Costa Rica. The list breaks down the countries as follows:
Group I - No visa required and up to 90-day stay
Group II - No Visa required and up to 30-day stay
Group III - Visa Required and up to a 30-day stay
Group IV - Restricted Visas - may only enter with pre-approved visa

Extension of legal stay beyond that time requires application to the Costa Rican Department of Migration. Tourists who have overstayed their 90-day limit without receiving a formal extension can expect to be fined at the airport as they depart the country. Those who have overstayed repeatedly, or have overstayed and wish to depart Costa Rica by land, must pay a fine to migration authorities in San Jose before departure. There is a departure tax for short-term visitors.

Minors born in Costa Rica, even if they are citizens of other countries traveling on passports of those other countries, are considered to be citizens of Costa Rica. They are thus required by Costa Rican officials to comply with all laws regarding the international travel of Costa Rican minors. Parents of children born in Costa Rica are encouraged to consult with the Costa Rican Embassy or consulate about entry and exit requirements before initiating travel.

Source: Costa Rica Law.com