Newstalk ZB and ZM are the big winners in the latest radio ratings - hitting their highest-ever audiences.

Newstalk increased its overall audience by nearly 74,000 listeners in the latest GfK Commercial Radio Audience survey - a reflection of high levels of news interest during the Covid-19 period.

On the entertainment side, music network ZM now has the most listeners in the key audience groups of 18- to 34-year-olds and 25- to 54-year-olds, both of which are highly valued by advertisers.

Newstalk ZB and ZM, both owned by NZME, grew their Breakfast audiences and are now the two most popular commercial breakfast radio networks across New Zealand's major radio markets.

The latest increase in Newstalk ZB's nationwide audience takes the news and talk network's audience to more than 610,300 listeners, ZB's biggest audience since it was launched in 1987.

The Mike Hosking Breakfast further cemented its place as New Zealand's favourite morning radio show, growing by 33,100 listeners.

"It's incredibly humbling that so many New Zealanders looking for news and information they can trust, have turned to Newstalk ZB in such huge numbers during the Covid crisis and beyond," said NZME head of talk Jason Winstanley.

"We've had audience growth right across the day – with listeners looking for up to the minute news as well as the connection, companionship and conversations across our talk shows."

With its unique audience of 1,838,000 in September, NZME'S nzherald.co.nz is now New Zealand's number one digital news provider.

"That so many New Zealanders have turned to NZME's radio networks, our newspapers and websites during a time of such incredible uncertainty is a reflection of the tireless work put in by all of our people at NZME," said NZME chief executive Michael Boggs.

NZME made significant changes to many of its radio networks in the lead up to this radio survey period including the launch of the Jono & Ben Breakfast on The Hits, a new breakfast show on Coast with Jase, Toni & Sam, introducing a new 'Old School' music format on Hip Hop and RnB network Flava as well as the launch of a brand new 'Gold' network in July.

"All of the changes we've launched this year are part of a strategy aimed at delivering sustainable audience growth by making sure we have a relentless focus on our listeners," said NZME chief radio and commercial officer Wendy Palmer.

"This means having the best radio hosts in New Zealand on the best networks.

Palmer singled out the strong performance of entertainment brand ZM.

"The ongoing growth of the popularity of ZM reflects the incredible dedication of its on-air, production and promotions teams to their audience," said Palmer.

"ZM continues to go from strength to strength, now with 523,600 listeners nationwide - a new high for the network."

Music network ZM now has the most listeners in the key audience groups of 25-44 year olds and 25-54 year olds across New Zealand. (Photo / File)

NZME's broadcast audience growth has been mirrored on its digital audio platform iHeartRadio which recently clicked over a million registered users. Listening data shows that since the lockdown commenced, iHeartRadio listening has grown - last week there was a high of nearly two million streams and 1.18 million total listening hours.

New Zealanders also took to podcasts in huge numbers across the Covid lockdown periods. In March this year, iHeartRadio podcast listens increased by 25 per cent compared to February. Downloads and listens now total nearly 1.6 million each month. The top three podcasts are Newstalk ZB's Mike Hosking Breakfast, The Fletch, Vaughan and Megan Show from ZM and The Matt & Jerry show from Radio Hauraki.

Boggs said these results reflected the trust New Zealanders have in these radio brands.

"Kiwis are trusting us to deliver the news and information and the connections they need across all of the devices they choose to listen on," he said.

"It is an incredible privilege and an incredible responsibility to continue to earn the trust New Zealanders place in us to keep them in the know."

NZME shares are currently trading at 64 cents, up from 40 cents on 1 September this year.