CatIQ Puts the September Southern Ontario Storm at C$563 Million in Insured Losses, Lower Than Many Expected

The first industry estimate for the severe storms that hit southern Ontario on September 2 and 3 puts insured losses at C$563 million. CatIQ, the Toronto-based catastrophe data subsidiary of PERILS, released the figure about three weeks after the event and published it on October 8. It covers commercial and residential property and motor claims and includes additional loss adjustment expenses. CatIQ describes the number as a snapshot of the insurance market at that point in time and expects it to develop as claims are processed.

The outbreak was a late-season event that ran across southern Ontario from Windsor to Ottawa. Reports describe very large hail, damaging wind gusts, torrential rain and flash flooding, with multiple confirmed tornadoes and downbursts. Toronto was among the hardest-hit locations, and the city of Vaughan, north of Toronto, saw severe flooding. Hail reportedly the size of ping pong balls and strong winds damaged the side of Rogers Stadium at Downsview Park, and flash flooding closed major roads and stranded motorists, some of whom needed rescue. CatIQ director Caroline Floyd said storms of this intensity, especially with large hail, rarely strike Toronto directly.

What surprised many people was the size of the loss, which is lower than some expected. Glenn McGillivray, managing director of the Institute for Catastrophic Loss Reduction, told Canadian Underwriter that the figure surprised people in his circles, who had expected something much larger. Some had speculated it would be Ontario's largest insured loss ever, and one group had estimated about C$1.5 billion. McGillivray called the lower number good news but noted that nearly C$600 million is still significant. He said the reason is unclear and offered speculation rather than conclusions: limits and sub-limits on basement flood coverage, and newer separated sewer systems in areas north of Toronto, could both have held down claims.

The comparison with the July 2024 Toronto flooding is instructive. That event brought roughly 100 millimetres of rain in a few hours, flooded highways, halted subway service and damaged buildings, and CatIQ's final estimate for it is C$890 million. Floyd said wind and hail played a larger part in the 2026 storms than in 2024, when flooding dominated, and that average personal and auto claims are currently lower than they were for the 2024 flood. The estimate is likely to move, and early estimates of any catastrophe can be revised up or down as late-reported claims arrive and adjusters inspect damage.

The loss also needs to be seen against a busy catastrophe season. Insurance Business reported that Intact Financial and Definity Financial have between them put third-quarter catastrophe losses at roughly C$850 million net of reinsurance. Intact estimated about C$660 million pre-tax, of which C$615 million was in Canada, C$38 million in the UK and Ireland and C$7 million in the US. By line, its losses were C$390 million in personal property, C$173 million in commercial lines and C$52 million in personal auto. Its trailing twelve-month catastrophe losses were C$1.29 billion, above its annual guidance of C$1.20 billion. Definity said catastrophe losses reduced third-quarter underwriting income by about C$190 million, or C$1.15 per common share, with personal property accounting for about 72% of the total.

Those figures include several different events. CatIQ estimates the June 30 to July 3 storms in southern Ontario and southern Quebec at C$491 million, much of it from basement flooding in Ottawa, and the Bald Range Fire near Summerland, British Columbia, at C$293 million. Other wildfires, rainstorm flooding in Ontario and Alberta, and the early September storm made up the rest. Taken together, they show how frequent mid-sized events, rather than a single mega-catastrophe, are driving Canadian insurers' results.

The Insurance Bureau of Canada argued on September 15 that Canadians should stop treating catastrophic flooding in the Toronto area as a surprise. Amanda Dean, the bureau's vice-president for Ontario and Atlantic Canada, proposed three steps: invest in infrastructure, shift from recovery to prevention, and give Canadians access to flood risk information. McGillivray added that 2026 has seen a lot of severe convective storm rainfall in Canada, and that the combination of heavy rain, strong wind and hail deserves more attention because in the United States it is the costliest such combination each year and is likely to worsen in Canada as the climate warms.

What does this mean for ordinary policyholders? Insurers do not set premiums off one storm, but a run of costly years raises the price of reinsurance and the cost of covering property, and those costs eventually show up in renewals. Homeowners can take practical steps now. Read your policy to see whether overland flood, sewer backup and hail damage are covered and what the deductibles are, since these are often separate from standard coverage. Photograph your home and keep an inventory of valuables, and ask your broker how roof age and material affect hail coverage. If you made a claim for the September storm, keep receipts for emergency repairs and respond promptly to adjusters, because large events can slow processing.

It is also worth being clear about what is not known. The C$563 million figure is initial and may change, no claim count has been published in the sources reviewed, and the reasons the number is lower than some predicted are speculation at this stage. CatIQ's later updates will show whether the final loss moves closer to the earlier guesses or settles near this first estimate.