Chubb says global diversification contributed to a strong half-year result, as it reported a 20% increase in profit to $US5.17 billion ($7.4 billion) for the six months to June 30.

The insurer has also reported a net profit of $US2.8 billion ($3.4 billion) for the three months to June 30, up 14%.

Chairman and CEO Evan Greenberg says property and casualty underwriting income for the half grew almost 19% to $US1.9 billion ($2.7 billion), with a combined operating ratio of 83.8%.

“In terms of P&C markets, overly soft underwriting conditions persist in certain areas of property insurance globally, particularly large accounts and excess and surplus-related,” he said.

The company has maintained underwriting discipline and is paying a “growth penalty” by not underwriting at a loss, but this will dissipate, he says.

Soft market conditions are spreading to areas of casualty, and financial lines remain soft, according to Mr Greenberg.

Life underwriting income grew nearly 9% to $US332 million ($473 million).

The combined group reported gross written premium of $US34.5 billion ($49 billion) for the six months, up 6.5%.

Net P&C premium rose 3% to $US12.77 billion ($18 billion) and life insurance premium grew 7.5% to $US1.9 billion ($2.7 billion).

Chubb has invested assets of $US175 billion ($249.5 billion), up 9%.