Earthquakes in Tonga — April 2026

18 earthquakes were recorded in Tonga during April 2026, an average of 0.6 per day.

18 reached magnitude 4 or above and 5 reached magnitude 5 or above. The average focal depth was 200 km.

The month's largest event in Tonga was a magnitude 6.1 earthquake near Hihifo, Tonga on 19 April 2026 at 17:34 UTC. A magnitude 6.1 earthquake radiates roughly 21,301 tons of TNT equivalent in seismic energy.

That is close to the Tonga monthly average of 18 events over the period we cover, and down from the 40 recorded the previous month.

22% of events here are shallow (under 70 km), 67% intermediate (70–300 km) and 11% deep-focus (over 300 km). That proportion of deep-focus events is the signature of a subduction zone: only a cold slab descending into the mantle stays brittle enough to rupture at those depths.

By band, the catalogue holds 13 in the magnitude 4 range, 3 in the magnitude 5 range, 2 in the magnitude 6 range.

Activity peaked on 28 April, when 3 events were recorded.

The month's largest events were M6.1 near Hihifo, Tonga on 19 April at 10 km; M6.1 near Hihifo, Tonga on 19 April at 36 km; M5.5 near Neiafu, Tonga on 13 April at 255 km.

That is close to the 18 events Tonga averages per month across the 21 months on record.