Chorus has said it will be upgrading its fibre users over the next three months to replace 100Mbps speeds with 300Mbps connections.
That means its 100/20Mbps plan will become 300/100Mbps, while the Business Evolve 100/100Mbps plan will become 300/300Mbps, and Small Business Fibre 100/100Mbps will be 500Mbps symmetric.
"The fibre build propelled New Zealand's broadband infrastructure well ahead of that in Australia, the UK and many other countries. However, some countries, where fibre is ubiquitous are starting to pull ahead," the company said.
The upshift could impact up to 600,000 premises, Chorus said.
"In 2011, at the start of UFB, 30Mbps was considered a great broadband speed. In 2015, as Netflix launched in New Zealand, 'great broadband' increased to 100Mbps," CEO JB Rousselot said.
"Our network traffic monitoring is showing that there are homes and businesses on fibre 100/20Mbps who regularly max out their broadband connection."
Chorus said it is consulting with New Zealand retailers to determine the best way to pass through the upgrade and expects most customers to see it in early December.
In its recent set of results, the broadband wholesaler said it was approaching 20% of its 860,000 fibre connections being on 1Gbps plans and has launched 8Gbps fibre in "select CBDs". In total, Chorus has 1.34 million connections around New Zealand, a drop from the 1.42 million reported last year.
Revenue for the company dropped NZ$12 million to NZ$947 million, earnings before interest, tax, depreciation and amortisation was steady at NZ$649 million, and net profit landed at NZ$47 million.
Last week, the NZ Commerce Commission released its winter edition of the Measuring Broadband New Zealand and found 1Gbps plans were clocking at 855Mbps during busy hours.
"We've enhanced the programme by adding a new test server in Christchurch that enables us to measure and report on performance in the South Island independently," Telecommunications Commissioner Tristan Gilbertson said at the time.
"The Christchurch server has confirmed that any differences in performance in the South Island are the result of many providers routing their traffic via the North Island.
"However, the difference in performance for high speed fibre plans is minor, and would likely not be noticeable for most South Islanders."