Newstalk ZB has grabbed a larger share of listeners across New Zealand - and in the key battleground of Auckland, according to the latest radio survey results.

The station also recorded a cumulative audience of 502,300 in the latest Gfk independent radio survey - the first time Newstalk ZB has ever cracked half a million listeners.

Newstalk ZB grew its market share in the survey to 11 per cent in Auckland and 10.3 per cent nationally.

ZB's Mike Hosking remained the most listened to commercial breakfast radio host in the country and grew his share across New Zealand and in Auckland.

The gap between the Mike Hosking Breakfast Show and the rival The AM Show widened in the survey from 7.8 per cent to 8.8 per cent of the market nationally.

Hosking has 339,600 cumulative listeners aged 10+ between 6am and 8:30am, compared to The AM show's 135,300.

NZME and its partners now has over 2 million listeners and the company's stations - which include ZB, ZM, The Hits and Flava - added 54,500 new listeners in the latest survey.

"This is an overall market share increase of 1.8 percentage points for NZME and Partners whilst MediaWorks went backwards for the second survey in a row... I'm particularly excited that alongside our radio partners, we are better reflecting the new diversity of New Zealand's population," said NZME's chief commercial officer Laura Maxwell.

NZME managing editor Shayne Currie says ZB continued its dominance - having been number one since 2003.

"This means we've again retained the number one crown, while the Mike Hosking Breakfast is the biggest breakfast show in the country," Currie said.

"Marcus Lush has also had a phenomenal result, being number one in all markets across the country," he said.

Another NZME station, Radio Sport, enjoyed the biggest growth of any station with an additional 21,200 listeners in the survey.

This was a testament to both the station's talent and NZME's integrated newsroom, Currie said.

"This absolutely shows the power of NZME. Our broadcasters, producers and reporters are across everything - delivering high-quality exclusive news and sport content and interviews that people want to listen to."

NZME also publishes the New Zealand Herald.