TV3 News says it has overtaken One News in the state broadcaster's key viewership of 25- to 54-year-olds.
AGB Nielsen figures for the month of September also show Campbell Live made a substantial ratings gain in the five main cities.
The results go against a perception that TV3was going downhill while TVNZ lifted its game this year.
TV3's director of News and Current Affairs, Mark Jennings, said it was winning viewers with a new high-tech, multi-purpose studio set and a no-nonsense and independent approach to political coverage.
However, TVNZ head of news and current affairs, Anthony Flannery, said September was its 11th consecutive month of year-on-year growth.
"We are over the moon with our performance," he said, adding that an average 220,000 more viewers tuned in to watch One News every night.
TV3 said in its important 18-49 years viewership it improved by 7.3 per cent to claim a 36.7 per cent share compared with One News falling 15.6 per cent to 29.2 per cent.
Among the 18- to 49-year-olds in the big cities, 3 News gained 13.1 per cent of the audience to 41.4 per cent. One News took a 23.5 per cent share.
In the 25- to 54-year-old demographic, 3 News picked up 9.7 per cent, bringing audience share to 35.1 per cent while One News dropped 14.1 per cent to 34.8 per cent.
TV3 said Campbell Live's share of 25- to 54-year-olds had grown to 21.2 per cent compared with Close Up's 20 per cent share. Mr Flannery said nationally Close Up outrated Campbell Live in the over 5-year-old group.
