Following severe storms and flooding in and around the country's largest city, Auckland, major insurers Insurance Australia Group and Suncorp Group have collectively received over 9,000 claims.

As of Monday morning, over 5,000 claims had been handled by IAG's AMI, State, and New Zealand Insurance brands compared to about 3,000 claims handled by Suncorp's Vero and AA Insurance brands.

On Sunday, Tower Ltd reported that it had received more than a thousand claims since Friday, noting that the losses were "substantial."

The Insurance Council of New Zealand claims that this is a significant event that will lead to numerous claims.

As the situation develops and customers report damages, insurance companies anticipate a further increase in claims in the upcoming days.

In the last three days, Auckland has experienced floods and landslides that have claimed the lives of four people and caused millions of dollars worth of damage. In the 1.6 million-person city, there is still an emergency situation.

Since Friday, Auckland has seen record amounts of rain, and the city's council predicts that rain will continue to fall heavily over the next few days.

In a tweet, the National Institute of Water and Atmospheric Research (NIWA) reported that Auckland has now seen 40% of its annual average rainfall and more than eight times the average January rainfall.

The shares of Tower, a company listed in New Zealand, fell 8.5% on Monday to NZ$0.650, the most since March 17, 2020.

IAG's stock fell 5.9%, on track to have its worst session in 15 months. While rival QBE Insurance, which has not yet disclosed information regarding claims received, fell 2.9%, Suncorp fell 2.8%.

IAG stated that it is still too early to determine the floods' financial impact and that once the situation is more clear, it may review the A$909 million ($645 million) in natural peril costs it has budgeted for the fiscal year 2023.

Given that its reinsurance program offers additional protection for New Zealand losses, Suncorp stated that losses from this event will be capped at NZ$50 million ($32.4 million).

IAG's exposure to the Auckland floods, which could be as high as A$236 million, is "much greater," according to Citi, than Suncorp's NZ$50 million cap.