A Samsung flag stands alongside a Korean flag outside the group's building in southern Seoul, Oct. 31. Yonhap

The financial arms of Samsung Group are continuing to earn more than the country's major banking groups, increasing their prowess even without owning a banking unit.

The five largest financial holding companies — KB, Shinhan, Hana, Woori and NH — remain lucrative by capitalizing on massive interest income reaped by their respective banking arms in a high borrowing rate era.

In this environment, Samsung Life Insurance, Samsung Fire & Marine Insurance, Samsung Card and Samsung Securities logged a net income of 4.6 trillion won ($3.3 billion) in the first three quarters of this year.

These four companies are among the largest affiliates of Samsung Group, which also includes Samsung Venture Investment, Samsung Asset Management and Samsung Futures.

The seven are collectively grouped under the name of Samsung Financial Networks.

The 4.6 trillion net income excludes the earnings from the smaller three affiliates. Nevertheless, the amount was higher than the net income posted by each of the five banking groups in the first nine months — 4.39 trillion won for KB, 3.98 trillion won for Shinhan, 3.22 trillion won for Hana, 2.65 trillion won for Woori and 2.31 trillion won for NH.

The findings came after the larger four affiliates of the Samsung Financial Network outpaced the five banking groups in the first half of the year.

Back then, the four reported a net income of 3.2 trillion won, compared to KB's 2.78 trillion won, Shinhan's 2.74 trillion won, Hana's 2.06 trillion won, Woori's 1.75 trillion won and NH's 1.75 trillion won.

Analysts note that the Samsung Financial Network is outperforming the banking groups thanks to record earnings made by its two insurance arms.

Samsung Life Insurance reported a net income of 2.42 trillion won for the January-to-September period, marking a remarkable 40.9 percent increase compared to the previous year and setting an all-time high.

The two Samsung insurers face a bright outlook. "The health insurance sector is growing as people live longer and pay more attention to well-being," an analyst said.

During the same period, Samsung Fire & Marine Insurance reported an aggregate net income of 1.86 trillion won, reflecting a 13.7 percent year-on-year increase and marking a record high.

Samsung Card reported a net profit of 531.5 billion won in the first three quarters, driven by its cost-cutting measures.

According to sources, this governance strategy is expected to help Samsung Card close the gap with Shinhan Card, the market leader.

After returning to profitability in the first half of the year, Samsung Securities reported a net income of 240.3 billion won for the first nine months. The earnings exceeded market expectations.