TOKYO -- Reeling from increased claims due to a spate of natural disasters, Japan's four major insurers plan to raise premiums on fire insurance policies for businesses by about 4% as early as January 2021.

The increase follows fresh hikes announced just last month.

At about the same time, individual policy holders will also be hit with hikes on similar policies, which cover fire, flooding and wind damage.

The four companies -- Tokio Marine & Nichido Fire Insurance, Sompo Japan Nipponkoa Insurance, Mitsui Sumitomo Insurance and Aioi Nissay Dowa Insurance -- are taking their cue from the General Insurance Rating Organization, which calculates the reference rates used to set premiums.

The expected hike comes as the country's insurers have faced increased payouts after a number of natural disasters battered the country.

Payouts for both corporate and individual policies in fiscal 2001 totaled around several tens of billion yen, and reached 744.9 billion yen ($6.82 billion) in fiscal 2004.

This spiked to the historic high of 1.57 trillion yen in fiscal 2018, due largely to damage inflicted by Typhoon Jebi.

This fiscal year, ending March 2020, the four insurers face heavy payouts from typhoons Faxai and Hagibis, pushing claims from these two disasters alone to well over 600 billion yen.

The full-year total "is highly likely to reach 1 trillion yen," including the impact from other disasters, such as the July flood in Kyushu, according to an executive of one of the insurers.