Global disasters have not made an impact on US commercial lines as strong capacity continues to fuel across-the-board premium falls, according to the Risk and Insurance Management Society (RIMS).

It says that despite natural catastrophes in New Zealand, Australia and Japan taking a sizeable chunk out of the global reinsurance market, premiums across the US property and casualty sector fell in the first quarter.

Property insurance fell 4.2%, workers’ compensation was down 3.2% and directors’ and officers’ dropped 2.3%. Prices in general liability were generally more stable, falling by just 0.8%.

RIMS says the latest survey of risk managers by Advisen shows the US market is still “highly overcapitalised”. While insurers are more prepared to walk away from underpriced business, “capacity remains at an all-time high”.

RIMS director Fred Savage says catastrophes have not affected US premiums yet, but that could quickly change.

“The earthquakes in New Zealand and Japan are reminders as to how vulnerable the US is to devastating earthquakes,” Mr Savage said.

“A big hurricane or earthquake could cause premiums across the board to change dramatically.”

Mr Savage says that barring a “horrendous” Gulf of Mexico hurricane season, 2011 could remain a buyers’ market.