Severe floods across NSW and Queensland will lead to an “influx” of claims, but will not hurt insurers’ credit ratings, S&P says.

The ratings agency says it is too early to estimate the full extent of the damage with further rain expected in some areas, and it will take weeks for many claims to be lodged.

But it says Australia’s largest insurers are well protected by reinsurance.

“While the ultimate losses for individual insurers will vary – depending on their exposure to the hardest hit areas, the declared number of events, and the structure of their reinsurance arrangements – we expect these to be manageable,” S&P said.

“We believe that Australia's [property and casualty] insurers are well-placed to assess and meet claims that arise with reinsurance protection shielding the larger insurers from outsized losses.”

S&P says Australia’s three largest primary insurers “have relatively low retentions” in the $150 million to $250 million range, before catastrophe reinsurance kicks in.