M7.5 earthquake 158 km W of Neiafu, Tonga

Tuesday, March 24, 2026, 04:37:51 UTC · 18.539°S, 175.476°W

A magnitude 7.5 earthquake struck 158 km W of Neiafu, Tonga on Tuesday, March 24, 2026, 04:37:51 UTC, at a depth of 234.0 km (intermediate). USGS received 19 “Did You Feel It?” reports, with a maximum reported intensity of V (moderate). The USGS PAGER alert is green: low likelihood of casualties and damage. It is the strongest earthquake within 300 km since an M8.2 on August 19, 2018.

Magnitude: 7.5; Major · mww
Depth: 234 km; Intermediate
Felt reports: 19; Max intensity V
Est. shaking: V; Moderate (ShakeMap)
PAGER alert: Green; Impact estimate
Tsunami: No flag; USGS feed

Outlined circle: this earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

2.7 megatons of TNT

That is about 178 times the Hiroshima bomb. It released about 5,623 times the energy of a magnitude 5.0.

Tectonic setting

54 km

from the nearest mapped plate boundary, between the Tonga and Niuafo'ou plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: intermediate

234 km

Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.

Did You Feel It?

Where it was felt

Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.

Place	Intensity	Reports	Distance
Nukuʿalofa, Tongatapu, Tonga	III · Weak	7	366 km
Neiafu, Vavaʿu, Tonga	V · Moderate	2	276 km
96799<br>0.320	IV · Light	2	728 km
Tofoa-Koloua, Tongatapu, Tonga	III · Weak	2	369 km
Pangai, Haʿapai, Tonga	IV · Light	1	290 km
Ohonua, Eua, Tonga	III · Weak	1	386 km
Maninoa, Rest of Upolu, Samoa	III · Weak	1	679 km

I felt it — report to USGS ↗

USGS PAGER estimate

Who was exposed to shaking

Modelled from the ShakeMap and population data. Alert level green: low likelihood of casualties and damage.

V · Moderate shaking: 23,000 people
IV · Light shaking: 82,000 people
III · Weak shaking: 1,500 people

Estimated shaking in nearby towns

NeiafuPopulation 7,400V · Moderate
KolovaiPopulation 4,100IV · Light
`OhonuaPopulation 1,300IV · Light
Nuku`alofaPopulation 23,000IV · Light

After the main event

Aftershocks within 200 km

USGS lists 25 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M5.4 on April 13, 2026. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 2,052 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 14 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:

1865M8.0
Tonga Islands
18 Nov 1865 · 234 km away
Limited damage (under $1M)tsunami
2006M7.9
Tonga Islands
3 May 2006 · 232 km away · intensity VII
Limited damage (under $1M)tsunami
2018M8.2
Fiji Islands
19 Aug 2018 · 286 km away · intensity V
tsunami
1903M8.0
Tonga Islands
4 Jan 1903 · 170 km away
1902M7.8
Tonga Islands
9 Feb 1902 · 225 km away
1919M7.8
Fiji Islands
1 Jan 1919 · 287 km away
tsunami

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers