On Wednesday Afternoon a Shallow M5.6 Earthquake struck in the North Pacific Ocean 264km from San José (Costa Rica).

Written by Earthquakelist.org on September 30th, 2026. Last updated October 21st, 2026.

A shallow and significant M5.6 earthquake struck in the North Pacific Ocean 264 kilometer from San José, Costa Rica in the afternoon of Wednesday September 30th, 2026. Roughly 110 thousand people may have felt this earthquake. Nicaragua is also near its epicenter.

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Earthquake Summary

This earthquake hit under water in the North Pacific Ocean, 85 kilometers (53 mi) off the coast of Costa Rica, 264 kilometer west of San José. The center of this earthquake had a very shallow depth of 8 km. Shallow earthquakes usually have a larger impact than earthquakes deep in the earth.

Date and Time:	Sep 30, 2026 03:55PM (Costa Rica Time) - Sep 30, 2026 21:55 Universal Time.
Location:	263 km south of Managua, Nicaragua. Coordinates 9°46'39"N 86°29'10"W.
Map:	Map of area around epicenter. Click to open in Google Maps.
Magnitude:	MAG 5.6 Detected by 27 stations. Maximum Error Range ±0.06 .
Depth:	8 km (5 mi) A very shallow depth.
Max. Intensity:	IV Light On the Modified Mercalli Scale.
Tsunami Risk:	Low tsunami risk Earthquakes under MAG-6.5 do not usually cause tsunami's. Always stay cautious - More info here.

Minimal impact predicted

Based on scientific estimates by the US Geographic Survey (USGS), the risk of high fatalities for this earthquake is classified at level GREEN (low). They expect an 90% likelyhood of between 0 and 1 fatalities.

The USGS classifies the economic impact of this earthquake at level GREEN (low). They expect an 90% likelyhood of between 0 and 1 million US Dollars in economic damage and impact.

Roughly 110 thousand people exposed to shaking

This earthquake may have been felt by around 110 thousand people. That is the expected population size of the area exposed to a level of shaking of II or higher on the Modified Mercalli scale according to the USGS.

The highest earthquake impact level for this earthquake is IV, which corresponds with light shaking and likely no damage. Roughly 63,970 people are expected to be exposed to this level.

People in 2 countries have been exposed to shaking. In Costa Rica , around 110 thousand people, with impact levels up to IV (light shaking, likely no damage). People were exposed to shaking in Nicaragua as well.

Nearby towns and cities

This earthquake struck within proximity of multiple countries. Costa Rica and Nicaragua are both within 300km distance of its epicenter.

The closest significant population center near the earthquake is Nicoya in Guanacaste, Costa Rica. Nicoya is located 121 kilometer (75 mi) west of the epicenter.

Multiple large cities are in proximity of today's earthquake. Managua is located 263 km to the north. San José is located 264 km to the east. Masaya is located 248 km to the north.

The table below provides an overview of all places in proximity of today's earthquake.

Overview of nearby places

Earthquake Intensity Map

The intensity in shaking and damage by this earthquake is illustrated through the map below. The highest intensity measured for this earthquake is IV.

I Not felt

II Weak

III Weak

IV Light

V Moderate

VI Strong

VII Very Strong

VIII Severe

IX Violent

X Extreme

Shaking reported by 3 people

People that feel an earthquake may report their experience to the US Geographic Survey. Currently, 3 people have reported shaking in 2 places in Costa Rica.We keep updating this article as more ground reports become available. You may report that you felt this earthquake here.

Places with most reports:

• San Rafael, San José, Costa Rica: 2 people.
• Sardinal, Guanacaste, Costa Rica: 1 person.

2 Aftershocks detected

After this earthquake struck, 2 smaller aftershocks occurred. Just 33 mins after this main shock, an earthquake measuring MAG-3.5 was detected 7 km (4 mi) south of this earthquake.

In the days before this main shock, 2 smaller foreshocks were detected. Roughly 1 day before this earthquake, a foreshock measuring MAG-2.7 was detected nearby this earthquake.

Overview of foreshocks and aftershocks

More earthquakes coming?

Earthquakes can create aftershocks. These are generally at least 1 magnitude lower than any main shock, and as time passes the chance and strength of aftershocks decreases.

In only six percent of cases, significant earthquakes are followed by a larger main shock, making the current earthquake a foreshock. While the chance of this happening is not so large, it is adviced to maintain cautiousness in the hours and days following a major earthquake.

Earthquakes like this are common in the region

Earthquakes of this strength occur quite regularly in the region. This is the strongest earthquake to hit since April 15th, 2026, when a 5.7 magnitude earthquake hit 19 km (12 mi) further north-east. An even stronger magnitude 6.6 earthquake struck on April 21st, 2022.

In total, 12 earthquakes with a magnitude of 5.6 or higher have been registered within 300km (186 mi) of this epicenter in the past 10 years. This comes down to an average of once every 10 months.

Low tsunami risk

Based on early data it appears this earthquake was not strong enough (lower than MAG-6.5) to be likely to cause destructive tsunami's. However this earthquake appeared to have hit at a shallow depth under sea, so stay cautious and monitor advice from local authorities.

Tsunami Risk Factors

Sources

Last updated 21/10/26 23:58 (). This article is automatically generated based on available data. We keep checking multiple sources for additional information. This article gets updated as new details on this earthquake become available.

1. US Geographic Society (USGS): Earthquake us6000tymj
2. European-Mediterranean Seismological Centre (EMSC): Earthquake 20260930_0000275
3. Geonames.org: World Cities Database
4. Google Maps: Static API
5. Earthquakelist.org: Historic Earthquakes Database

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