Freight volumes in all other areas increased, with the largest rise being in imported car units, which were up 19 per cent.
"The company's high productivity and proximity to market had been key factors in retaining existing business and attracting new customers," chief executive Tony Gibson said.
Gibbs said freight volumes were expected to continue to rise as Auckland's economy and population grew.
The company is extending the Fergusson container wharf to cater for longer ships. A new truck facility has been built to speed up container handling, and rail services to the inland port at Wiri have been quadrupled, resulting in 3000 fewer truck movements a month to and from the terminal. The port is also investing in rail and the off-port supply chain - at Wiri and Longburn intermodal freight hubs.
The company is also extending two berths on Bledisloe multi-purpose terminal to provide capacity for future growth.
Ports of Auckland
• First-half net profit after tax of $28.9 million.
• Container volumes up 3 per cent at 490,723 TEU (twenty foot equivalent units).
• Breakbulk volumes up 7.7 per cent at 3.08 million tonnes.
• Car volumes up 19 per cent at 118,765 units.