Telecom's 4G mobile services will go live in Auckland in October and in Wellington and Christchurch by Christmas.
In a statement this morning, the company said 4G LTE services would be extended half of its network in 2014.
"This is another way we are helping Kiwis get better connected," said Telecom retail chief executive Chris Quin.
"We are very pleased with the current network's performance across both voice and data and the feedback from our customers has been very positive.
4G services allow users to stream videos, download and upload files and browse mobile internet much faster than over existing networks.
Quin said that if the company is successful in the Government's auction of 700MHz spectrum later this year, then it would allow Telecom to "significantly improve coverage in rural areas"
"We intend to install 4G LTE on RBI sites that we build from early 2014," Quin said.
Chinese telecommunications giant Huawei has been selected by Telecom to build the 4G-capable mobile sites. Alcatel Lucent, which built Telecom's XT network - which was dogged with technical problems when it launched in 2009 - had also been working with Telecom on its 4G trial.
"Huawei's selection was based on two main factors. The first is that they have extensive experience, having built 73 LTE networks in 42 countries. The second is that they are truly pushing the boundaries of LTE technology," said Telecom's chief technology officer David Havercroft.
Vodafone in February announced the launch of new 4G mobile internet services.
It is now live for Vodafone customers in parts of Auckland and the network will expand to more suburbs across the city weekly. It says 4G will be live in parts of Christchurch in May, and parts of Wellington in August and September this year.
2degrees has yet to announce when it will roll out its 4G services.