Port of Tauranga - New Zealand's largest freight gateway - today announced it is on track to become the first port in the country to transport more than 1 million containers in a single year.

"Our results show the Port of Tauranga is continuing to reinforce its position as the country's premier freight gateway," said chairman David Pilkington.

The port announced a healthy 8.5 per cent lift in group half year net profit to $41.9 million from $38.6 million a year ago, and revenue up 2.8 per cent to $125.3 million. Volumes in the six months to 31 December were up eight per cent on the previous comparable period to 11 million tonnes.

The board declared an interim dividend of five cents per share, up 8.7 per cent on the prior year's interim dividend.

"We have lifted revenue and earnings and moved record cargo volumes including more than 510,000 TEU containers," said Mr Pilkington.

"Exporters, importers and the shipping lines are increasingly recognising the benefits of our deep-water port and our efficient freight handling and stevedoring operations."

Mr Pilkington said the port expected to become the first New Zealand port to handle more than 1 million containers in a 12-month period in the 2017 financial year.

"This achievement is the direct result of our now-completed five-year $350 million infrastructure investment programme, which has extended the port's freight hinterland across the country, prepared the port for large ships and provided importers and exporters with highly-efficient routes to the country's most important markets. Our world-class infrastructure will benefit the New Zealand economy for years to come."

Chief executive Mark Cairns said the port was consolidating its position as the port of choice for international shipping lines, with ship visits in the six-month period rising four per cent to 774 from 741 in the same period last year.

Following completion of the dredging programme in September 2016, Maersk introduced a large vessel service, with Tauranga as it's only New Zealand call. The 9,500 TEU Aotea Maersk had been a regular visitor since October.

Meanwhile, Hamburg Sud last month announced it would introduce a big-ship peak-season weekly service next month, with Tauranga as its only New Zealand call. The largest cruise ship ever to visit the Bay of Plenty, the 4,700 passenger, 1,600 crew Ovation of the Seas also made its maiden voyage to Tauranga on Boxing Day.

"It is pleasing to see shipping lines take advantage of the possibilities created by the harbour dredging programme to bring in larger vessels," said Mr Cairns.

"The economies of scale that come with larger ships drive transport efficiencies and ensure New Zealand exporters retain direct routes to international markets. With bigger ships calling at Tauranga, we are handling significantly larger volumes of cargo per shipment.

"We continue to lead the way in setting productivity standards for the New Zealand port industry and we strive to look at all aspects of the container terminal operations to ensure that we remain cost-effective."

The port quoted Ministry of Transport figures from the fourth quarter of the 2016 calendar year showing a crane rate for the quarter of 35.9 container transfers per hour, compared with the weighted national average of 33.7 moves per hour.

"Our ship service rate was 89.8 container exchanges per hour per ship, compared with the national weighted average of 76.9. Such strong results, which rank Port of Tauranga in the top tier of Australasia's most productive ports, are not only good for our shareholders, they are also in the best interests of the New Zealand freight industry."

Port of Tauranga - six months to December 31, 2016

-Revenue: up 2.8% to $125.3 million.

-Net profit: up 8.5% to $41.9 million

-Total trade: Up 8% from 10.1 million tonnes to 11.0 million tonnes

-Container volumes: Up 8% to 510,074 TEUs