A magnitude 5.5 earthquake struck off the Pacific coast of El Salvador on 13 August 2026, with the United States Geological Survey (USGS) placing the epicentre 69 kilometres south-south-west of the town of Chirilagua, in the eastern department of La Unión. The quake occurred at 00:30:04 UTC (around 18:30 local time on 12 August, given El Salvador's UTC-6 offset), at a depth of 56.8 kilometres, and was recorded at coordinates 12.6084°N, 88.2864°W. The USGS logged the event using a moment magnitude (Mww) solution, drawing on data from 38 seismic stations and 42 analysed phases, and classified the report as "reviewed", its highest confidence tier for rapid post-event assessment.

The earthquake's offshore, moderately deep location put it well clear of the nearest coastal communities, and the USGS issued a green PAGER alert, indicating no significant casualties or damage were expected. No tsunami was generated. The agency's "Did You Feel It?" system had logged 15 felt reports shortly after the event, with a reported Community Decimal Intensity of 3.4 and a modelled Modified Mercalli Intensity of around 4.4, corresponding to light shaking near the epicentral area — consistent with a moderate quake centred well out to sea. The earthquake sits within a seismically active zone associated with subduction of the Cocos Plate beneath the Caribbean Plate along the Middle America Trench, a region that regularly produces earthquakes of this size. As of the latest USGS update, no injuries, deaths or structural damage had been reported in connection with the event.