TelstraClear is expecting 20% growth in the broadband business from the continued opening of Telecom's exchanges.
The Australian-owned company has almost doubled the size of its network by gaining access to 42 exchanges - 23 in Auckland and 19 in other centres, such as Palmerston North - or more than 220,000 houses and firms.
An additional 20 exchanges will be live by the end of next month, makibng 63 in total.
Chief executive Allan Freeth says this approach is profitable and others are still being analysed.
Separately in Australia, Telstra has threatened to oppose government reforms to the telecoms sector if they undervalue its asset base. It has urged the federal parliament to delay them.
Telstra is in talks with the government over splitting its fixed-line assets from the rest of its business and contributing these assets to a $A43 billion national broadband network.