US property and casualty rates increased 4% in October, according to US insurance exchange MarketScout.

This compares with a 5% increase in August and September this year and 4% increases for the preceding three months.

Commercial property, business owners, general liability and commercial auto were up 5%. Business interruption, professional liability and D&O liability were up 4%, while crime and fiduciary were up 2%.

Rates for small accounts under $US25,000 ($24,032) increased 5%, while jumbo accounts over $US1 million ($961,000) were more competitive at 3%. Medium and large accounts, from $US25,000 to $US1 million ($24,033 to $961,000) increased 4%.

In personal lines rates increased 3%, the same as in August and September.

Homeowners insurance for properties valued over $US1 million was more competitive, increasing 2%.

MarketScout CEO Richard Kerr said although October was stable, Hurricane Sandy will affect rates for commercial and personal business in November, particularly in the northeastern states.

“Many of the flood claims will be paid by the National Flood Insurance Plan but some insurers did provide excess flood coverage,” he said.

The storm also caused wind, fire, property, loss of use and auto claims, he said.