Santam said its corporate business unit had made a loss in the six months to the end of June after a high number of industrial and fire-related claims squeezed its underwriting margin.
The company's investment division had performed significantly below levels achieved in the year-ago period due to a sharp slide in the value of its equity portfolio, it said.
Santam said it had been especially hard hit because its equity portfolio is overweight in financial and industrial stocks, but underweight in better-performing resource shares such as miners.
Shares in Santam fell 4 percent to 72 rand by 13:47, lagging a slightly firmer Johannesburg index of financial stocks.
The company said the underwriting performance of its personal and commercial businesses, as well as specialist units, met or exceeded expectations in the period. - I-Net Bridge