Along the Wadati–Benioff zone, earthquake activity has been observed as shallow, intermediate, and deep-focus events at depths of up to 700 km (430 mi).

[4] This subduction zone is one of the most active plate boundaries globally, moving at a rate of approximately 170 mm (7 in) per year.

[5] While much of the island arc experiences intermediate-depth earthquakes along a Wadati–Benioff zone that dips steeply at 70°, the area adjacent to the D'entrecasteaux Ridge does not.

[31] Two reservoirs[32] and the Port Vila Central Hospital were also damaged, forcing the transfer of patients to a military camp.

Landslides were also reported in outlying villages and islands, while three bridges were damaged to a point that they were at high risk of collapsing in case of heavy rain.

[22] Websites of Vanuatuan government agencies went offline, while communication lines for police and related authorities were rendered unserviceable.

[39] Extensive crop damage was recorded in Mataso due to landslides that buried gardens, sparking concerns over food shortages.

[19] The United Nations Office for the Coordination of Humanitarian Affairs estimated that 116,000 people had been directly affected by the earthquake,[44] equivalent to a third of Vanuatu's population.

[47] The Recovery Operation Centre estimated that the amount needed to recover from the earthquake reached 29 billion vatu (US$231.7 million).

[49] The education ministry said 45 schools were damaged, including Malapoa College, with rebuilding costs estimated at more than US$8 million.

[15] A survey by the Vanuatu Chamber of Commerce found that the extended closure of downtown Port-Vila had left 900 people unemployed.

[29] The Vanuatu National Disaster Management Office told residents of coastal areas to flee to higher ground.

[24] The central business district of Port Vila was closed off, while a boil water notice was declared over the city.

[37] A seven-day state of emergency[54] and a nighttime curfew[28] was declared by Prime Minister Charlot Salwai, who also requested international assistance.

[61] On 18 December, a Lockheed C-130 Hercules of the Royal New Zealand Air Force carrying an urban search and rescue team to Vanuatu was diverted to Nouméa in New Caledonia due to an engine fire warning.

[64] This alongside the deployment of an urban search and rescue team, Ministry of Health staff, as well as New Zealand Red Cross personnel, with the latter providing satellite phones and Starlink devices.