Chubb has forecast a $US372 million ($521.95 million) net catastrophe loss for the current quarter.

It says more than 20 natural disasters, including hurricanes and rainstorms in the US, Japan and southeast Asia and wildfires in California, are responsible for the loss.

Losses have occurred mostly in commercial and personal property lines, casualty business and reinsurance.

Chubb will reveal its overall third quarter earnings on October 24.  

It previously reported $US2.38 billion ($3.34 billion) net income for the six months ending June 30.