Natural and man-made disasters cost $92 billion (€81.24 billion) in 2015, compared with $113 billion in 2014, the Swiss reinsurer Swiss Re said in report today.
Global insured losses were $37 billion, far below the $62 billion annual average of the last 10 years, it said.
The biggest single insured-loss of the year was the twin explosions at the port of Tianjin, northeastern China, in August which was estimated to cost between $2.5 and $3.5 billion.
This was followed by a storm in the US in February, which left insurers with a bill of $2.1 billion.
Out of 353 disaster events, 198 were natural catastrophes, the highest number in any one year, Swiss Re said.
The report is the final version of a preliminary estimate last December which said all disasters in 2015 cost $85 billion.
Around $80 billion of the $92 billion losses came from natural disasters, led by the earthquake in Nepal, which cost $6 billion - a figure that includes damage reported in India, China and Bangladesh.
The earthquake killed nearly 9,000 people, making it the deadliest single disaster event in 2015.
The Swiss Re report said the blasts in Tianjin, which also killed 173 people, were the costliest insurance loss event ever in Asia, and the third costliest worldwide.
This list is headed by the 9/11 terror attacks on the US, estimated at $25.2 billion.
The Tianjin disaster "has put a spotlight on accumulation risk in large transportation hubs such as ports," the report noted.
"The imposition of an exclusion zone at the site due to the risk of follow-up explosions and clean-up operations made it very difficult for insurers to assess the losses arising from the many damaged or destroyed assets, such as the many cars in transit at the port," it said.