Tower has returned to profit as higher premiums, better weather in the Pacific and its digital transformation, begin to pay off.
The insurance company made a net profit of $11.9m in the six months to March, compared with a loss of $11.6m in the same period last year, which was largely caused by a one-off reinsurance settlement.
Revenue from insurance premiums rose 8.9 percent on last year, while it paid out fewer claims. However, outstanding Canterbury earthquake claims cost it $4.7m.
Tower chief executive Richard Harding said its growth would allow it to compete with international insurers.
"Our drive to become a digital insurer and our fairer approach to pricing has seen online sales increase significantly.
"After a number of years of removing legacy issues and creating a solid platform for growth, we are now well placed to take on the large, overseas-owned insurers," Mr Harding said.
Tower expected net profit for the full financial year to be more than $26m.