South Korean insurance companies posted a 6.3 percent gain in combined first-quarter net profit helped by an increase in insurance premium income, government data showed Thursday.

For the three months ending March 31, the country's 25 life insurers and 32 non-life insurers posted 2.235 trillion won ($1.89 billion) in combined net profit from 2.103 trillion won a year earlier, the Financial Supervisory Service said in a statement.

"In the first quarter, the insurers' insurance premium income exceeded their insurance payments. That helped them post a quarterly net income growth. But they suffered declines in profitability due to unfavorable business environments," an FSS official said.

The return on assets, a key gauge of profitability, edged down 0.03 percentage points to 0.93 percent, while the return on equity, another index measuring profitability, fell 0.07 percentage points to 9.36 percent, the statement said.

"Record low rates drove down the profitability of assets under the companies' management," it said. (Yonhap)