Shares in specialist insurer Hiscox (LON:HSX) shot up over 7 percent on Monday morning, after a boost to premiums had a positive impact on profits.

For the half year to June 30th, pre-tax profit rose 27 percent to $163.6 million, on the back of a 20.3 percent increase in gross written premiums to $1,155.8 million.

Premiums at the insurer rose across all three of its main businesses, with retail gross written premiums up 19.6 percent  and London Market gross written premiums up 15.9 percent.

The first-half investment return was $19.7 million, compared with $58.5 million the previous year.

“The London market business is navigating the market and finding opportunities in areas such as flood, cyber and general liability,” Hiscox said.

“In reinsurance we have grown and are achieving good margins. The retail businesses, in their respective regions and product lines, continue their good momentum. The opportunities are legion.”

The company declared an interim dividend of 13.25 cents a share, up 5 percent on last year.

“It has been a good start to the year. Our investment across the business is driving strong profitable growth in all segments. We are on track to exceed one million retail customers in 2018,” said Bronek Masojada, Group CEO.

Shares in Hiscox are currently trading up 7.54 percent at 1,584.00 (0900GMT).