Zurich Financial Services is now estimating its losses from the US terrorist attacks are between $700m to $900m, up from its $400m estimate shortly after the attacks.
This is the largest loss ever experienced by the company. Its US direct non-life and reinsurance businesses will bear the brunt of the costs.
Zurich is warning of further income falls through lower capital gains and investment income, as well as reduced earnings businesses linked to equity markets such as asset management and life insurance.
But the group says it is financially strong enough to match the losses.