Chorus shares have jumped as much as 12% as the company welcomed a sweeping review of telecommunications regulation, saying it is a positive step for the industry.
The Government appears to have bowed to pressure by bringing forward the review, which was planned for September this year.
Communications and Information Technology Minister Amy Adams announced on Friday the review would start immediately.
The review comes days after the Commerce Commission proposed to cut the price Chorus can charge customers using its copper network, prompting Chorus to call for a review of the legislation, saying it will cost the company $160 million a year.
Chorus is the Government's major broadband partner and network provider.
The company was split from Telecom in 2011 and is taking a leading role in building the $1.5 billion Ultra Fast Broadband network in towns and cities, and the $300 million broadband upgrade in rural areas.
The review will look at all regulation, including the controversial levy which Telecom gets from rival supplying services to unprofitable rural customers.
In a statement, Ms Adams says the review will provide certainty for the industry and consumers.
Chorus chief executive Mark Radcliffe says he hopes the review will shape a new environment which will drive growth, and innovation enabled by a fibre broadband services.