Munich Re on Tuesday said insurers were likely to pick up only a small portion of the tab as the disaster affected mainly under-developed regions.
It renewed calls for action to fight climate change, which it blamed for a rise in such catastrophes.
"The terrible effects spreading all around the Indian Ocean and reaching as far as the Horn of Africa are a further reminder of the global threat from natural catastrophes," executive board member Stefan Heyd wrote in Munich Re's annual disaster report.
"They underline our long-standing demand for prompt and rigorous measures against global climate change. After the disappointing outcome of the recent climate summit in Buenos Aires, time is running out."
The world's biggest quake in 40 years, measuring 9.0 on the Richter scale, had caused total economic damage - both insured and uninsured - of more than $13.6 billion, the head of Munich Re's geo risks research department estimated.
Huge tidal waves devoured vast
regions across several nations
Gerhard Berz said the estimate was based on a "gut feeling" since reliable numbers were not yet available.
Munich Re estimated its own claims losses from Sunday's seaquake, which ravaged coastlines from Indonesia to Sri Lanka and India to East Africa, at less than 100 million euros, since high-value insured property was mainly confined to tourist and harbour areas.
"In spite of the long coastlines affected, the burden on the insurance industry will be limited. The reason for this is that seismic flood waves do not usually reach much further than a few hundred metres inland," it said.
"What is more, in the majority of these countries, the earthquake risk including tsunamis is excluded in property insurance policies and additional covers - as well as life and health insurance - are quite unusual."