The National Emergency Commission (CNE) reported no casualties, injuries or structural damage following a magnitude 5.1 earthquake that shook parts of the country Tuesday night.

The quake struck at 9:49 p.m. at a depth of 39 miles, with an epicenter about 3.7 miles southeast of Acosta canton in San José province, according to the Volcanological and Seismological Observatory of the National University (Ovsicori).

Three aftershocks were recorded within the first hour after the main tremor, with magnitudes ranging from 2.1 to 3.2, Ovsicori said.

Seismologists linked the earthquake to tectonic activity involving the Cocos Plate, an oceanic plate beneath the Pacific Ocean off Central America’s western coast. Named after Cocos Island, the plate is responsible for much of the region’s seismic activity.

Earthquakes along Costa Rica’s central Pacific coast are common and may originate either in the subduction zone or on local faults within the continental crust, Ovsicori noted.

Costa Rica’s Seismic Alert and Early Warning System, known as SATT and developed by Ovsicori, remains active and provides residents with real-time alerts on potential seismic activity.

Authorities continue to emphasize the importance of earthquake preparedness. In August 2025, the CNE coordinated the National Emergency Evacuation Drill to strengthen disaster response and educate the public on safety measures for emergencies, including earthquakes, floods, hurricanes, wildfires, landslides and volcanic eruptions.

Costa Rica experiences an average of about 400 earthquakes each month, making it one of the most seismically active nations in the region, according to experts.

The strongest earthquake ever recorded in Costa Rica occurred on April 22, 1991. Known as the Limón Earthquake, the magnitude 7.7 tremor struck the  La Estrella Valley in Limón province at 3:57 p.m. It was felt from Nicaragua to Panama and caused 48 deaths in Costa Rica and 79 in Panama.

Ovsicori is a research institute of the National University of Costa Rica dedicated to monitoring volcanic and seismic activity.

The CNE works with communities and emergency responders to strengthen the country’s preparedness, response and recovery capabilities during natural disasters.

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