Istanbul floods cause over $91 mn in insured losses after record rainfall

Severe flooding across Istanbul and five other Turkish provinces has generated more than 3,000 insurance claims following exceptionally heavy rainfall on October 13-15, 2026, according to a catastrophe report by Aon.

The storms brought what may have been Istanbul’s worst flash flooding in at least 80 years, inundating residential and commercial properties, damaging vehicles and roads, and disrupting ground and air transportation. Thousands of residents were evacuated as floodwaters swept through parts of Turkey’s largest city.

• Insurers received more than 3,000 claims following severe flooding across Istanbul and five other Turkish provinces on October 13-15, 2026, according to Aon.
• Insured losses in Istanbul exceeded ₺4.5 bn ($91 mn) by October 21, while insurers separately reported nearly ₺2 bn in reserves for fire and motor insurance claims.
• At least eight people died, approximately 2,000 homes and 900 businesses suffered serious damage, and nearly 20,000 property damage reports were submitted to authorities.

Cleanup operations and damage assessments remain underway, and Aon cautioned that it was too early to provide a reliable estimate of the event’s total losses.

According to figures from the Insurance Association of Türkiye (TSB) cited by Aon, insured losses in Istanbul alone exceeded ₺4.5 bn ($91 mn) as of October 21.

Separately, insurance industry figures published on October 26 showed companies had established reserves of nearly ₺2 bn against reported flood and inundation claims across Istanbul, Kocaeli, Sakarya, Yalova, Bursa and Antalya.

The reported reserves, equivalent to approximately $38 mn to $40.4 mn in the cited reports, relate to specific claims recorded under fire and motor insurance policies. They differ in scope and measurement from the broader insured-loss figure reported for Istanbul.

Istanbul records its heaviest rainfall in more than 80 years

The flooding followed intense rainfall that officials described as the heaviest recorded in Istanbul since meteorological records began in 1942.

The downpours intensified on October 14, triggering flash floods that swept vehicles through streets and inundated homes, businesses and transport infrastructure.

The Istanbul Metropolitan Municipality separately reported that some districts experienced their heaviest rainfall since 1985.

Videos from the affected areas showed parked cars being carried away by fast-moving floodwaters, while emergency responders rescued residents trapped in buildings and streets.

In the northern district of Sarıyer, footage showed vehicles being pushed into torrents of muddy water. Other recordings captured people being pulled through first-floor windows to safety.

In another rescue, two people carrying umbrellas were lifted away from floodwaters in the bucket of a mechanical excavator.

The disaster extended beyond Istanbul into neighbouring provinces in the Marmara region, including Kocaeli, Sakarya, Yalova and Bursa. Antalya, on Türkiye’s southern Mediterranean coast, was also affected.

A two-storey building reportedly collapsed in Sakarya, while Kocaeli recorded the second-highest volume of flood-related insurance claims after Istanbul.

Floods leave eight dead and thousands of properties damaged

The flooding caused substantial casualties and property destruction across the affected provinces.

Istanbul governor Davut Gül said six people had died in Istanbul, while the bodies of two additional victims from neighbouring Kocaeli province were recovered on the southeastern outskirts of the city.

Earlier reports had confirmed two deaths, including a 14-year-old boy who was electrocuted after stepping into a puddle in Istanbul’s Balat neighbourhood.

The teenager was taken to hospital but could not be saved. Three other people were reported to be receiving hospital treatment during the initial emergency response.

Authorities subsequently received approximately 20,000 reports of property damage associated with the rainfall and flooding.

We experienced a disaster that generated around 19,300 reports, each with different types of problems. At this point, it has been determined that around 2,000 homes and about 900 businesses … have suffered serious damage.

Davut Gül, Istanbul governor

Emergency services were deployed across the city as flooding affected residential districts, commercial premises and major transport routes.

Türkiye’s Disaster and Emergency Management Authority (AFAD) established a crisis coordination centre to manage incidents associated with the rainfall.

By the evening of October 14, emergency authorities had recorded 1,277 flooding incidents, 15 landslides, 47 people stranded and two roofs damaged or blown off.

Authorities also closed schools across Istanbul until Monday, October 19, urging residents to remain indoors unless travel was essential.

People living in basement properties were advised to move to higher floors, while residents were warned to avoid streambeds, underpasses and other locations exposed to flash flooding.

Turkish insurers allocate nearly ₺2 bn to flood claims

Insurance companies established reserves of more than ₺1.9 bn against 2,379 flood-related damage files, according to figures reported by Anadolu Agency and the Insurance Association of Türkiye.

The reserves represent amounts insurers estimate they will owe on reported claims, rather than compensation already paid to policyholders.

The fire insurance branch, which includes property, natural catastrophe and household coverage, accounted for the largest share.

Insurers reserved approximately ₺1.56 bn against 1,638 fire insurance claims. Comprehensive motor insurance accounted for a further ₺345.75 mn in reserves across 741 claim files.

Istanbul represented the largest concentration of expected insured losses in both business lines.

Within the fire insurance segment, reserves attributable to Istanbul reached approximately ₺1.39 bn, compared with ₺164 mn in Kocaeli.

Istanbul also accounted for approximately ₺312 mn of the motor insurance reserves. The figures indicate that property damage represents the majority of the losses identified in the detailed insurance association data, although motor vehicle damage remains a significant component.

The association’s separate October 21 figures, cited by Aon, placed insured losses in Istanbul above ₺4.5 bn. The available reports do not fully reconcile that estimate with the narrower reserve data disclosed for specific insurance branches.

More than 2,400 property and motor damage notifications

The insurance association also provided detailed figures on the number and distribution of reported claims.

Policyholders had submitted 2,453 damage notifications across the affected provinces, including 1,703 under fire insurance and 750 under comprehensive motor coverage.

In the fire insurance branch, Istanbul accounted for 1,486 notifications. Residential policyholders submitted 821 notifications, commercial customers filed 563, and industrial policyholders reported 102 incidents.

Only 12 fire insurance claims in Istanbul had received payments at the time of the report, with total compensation reaching ₺382,886. Of those payments, 11 related to residential claims and totalled ₺378,263. One commercial insurance claim had been paid, amounting to ₺4,623.

No payments had yet been recorded for the 102 industrial notifications. Outside Istanbul, Kocaeli recorded 179 fire insurance notifications, with one residential claim payment of ₺6,649. Yalova registered 18 notifications, Antalya 14 and Bursa six. Across all affected provinces, insurers had paid 13 fire insurance claims totalling ₺389,535.

No compensation payments had yet been recorded in the comprehensive motor insurance branch. Motor insurance notifications were concentrated in Istanbul, where policyholders filed 670 claims.

Kocaeli and Antalya each recorded 35 motor claims, followed by Sakarya with nine and Yalova with one. No motor insurance notifications were reported in Bursa.

Although insurers had established substantial reserves, the limited number of settled claims indicates that most reported losses remained under assessment at the time of the disclosure.

Flooding disrupts Istanbul airports and transport networks

The severe rainfall also caused extensive disruption to transport operations, including flights serving Istanbul’s two principal airports.

The Turkish transport ministry reported that 43 flights bound for Istanbul Airport, located near the Black Sea coast, were diverted because of the weather.

Another three flights destined for Sabiha Gökçen Airport, on the Asian side of Istanbul, were redirected.

Sabiha Gökçen also temporarily suspended departures because of strong winds. Road transportation was disrupted as floodwaters inundated streets and underpasses, leaving vehicles stranded or swept away.

Emergency crews worked to remove debris, rescue trapped residents and restore access to flooded neighbourhoods.

The disruption added to the economic consequences of property damage, although reliable estimates of uninsured losses and the broader financial impact were not yet available.

Government authorities also began distributing emergency financial assistance to affected residents.

According to Governor Gül, payments of ₺10,000 each were made to 5,200 residents. Authorities planned to provide the same amount to another 2,500 people on Monday, October 19.

These government assistance payments are separate from compensation owed under private insurance policies.

Istanbul floods compared with the 2009 catastrophe

The Insurance Association of Türkiye compared the October 2026 disaster with the severe flooding that struck Istanbul in 2009. That earlier event generated approximately 9,600 insurance claims, according to the association.

The latest floods had already produced more than 3,000 claims by the time of Aon’s catastrophe report, although the final number may change as insurers continue receiving and processing notifications.

The rainfall measurements also distinguish the latest event from previous flooding episodes.

Officials described the October 2026 precipitation as the highest recorded in Istanbul since 1942, while municipal authorities identified record rainfall in some districts dating back to 1985.

The extent of damage across residential, commercial, industrial and motor insurance portfolios will become clearer as inspections and claims assessments proceed.

For insurers, the immediate financial exposure includes damaged buildings, business premises and vehicles across six provinces, with Istanbul accounting for the largest reported share.

Aon’s catastrophe assessment cautioned that a reliable overall loss estimate could not yet be established. Insurers continue to evaluate reported damage, establish reserves and process compensation payments following one of Istanbul’s most severe recorded rainfall events.