Earthquakes in Puerto Rico — December 2025

172 earthquakes were recorded in Puerto Rico during December 2025, an average of 5.5 per day.

2 reached magnitude 4 or above and 0 reached magnitude 5 or above. The average focal depth was 22 km.

The month's largest event in Puerto Rico was a magnitude 4.2 earthquake near San Antonio, Puerto Rico on 05 December 2025 at 19:32 UTC. A magnitude 4.2 earthquake radiates roughly 30 tons of TNT equivalent in seismic energy.

That is close to the Puerto Rico monthly average of 173 events over the period we cover, and up from the 102 recorded the previous month.

96% of events here are shallow (under 70 km), 4% intermediate (70–300 km) and 0% deep-focus (over 300 km). Almost everything here is crustal. That is characteristic of transform faulting or continental deformation rather than subduction — and it means shaking at the surface is strong for the magnitudes involved.

By band, the catalogue holds 25 in the magnitude 1 range, 101 in the magnitude 2 range, 44 in the magnitude 3 range, 2 in the magnitude 4 range.

Activity peaked on 04 December, when 13 events were recorded.

The month's largest events were M4.2 near San Antonio, Puerto Rico on 05 December at 47 km; M4.0 near San Antonio, Puerto Rico on 05 December at 38 km; M3.8 near Suárez, Puerto Rico on 03 December at 55 km.

That is close to the 173 events Puerto Rico averages per month across the 21 months on record.