Wellington mayor Kerry Prendergast is seeking a fourth term in office, saying colleagues, business leaders and people in the street have asked her to stay in the job.
Her decision sets up a political fight with businesman Sir Bob Jones, who says he will form a political team for the election in October.
He is campaigning for a ban on vehicles in the central city, and the creation of a pedestrianised golden mile.
The millionaire businessman had invited the mayor to support his initiative, but Ms Prendergast she says she would prefer to campaign across a number of issues.
"I've always stood as an independent, I think that's what Wellingtonians want. I don't want to be run by group with just a single vision.
"I think there are bigger issues facing Wellington at the moment and of course our position after the Auckland super-city's in place in October is just one of those."
Meanwhile, Sir Bob says he is drawing up a list of candidates to run on his ticket which will be announced in May.
"I'm very much of the view that ... you can take people out of nowhere and they can win mayoralties", he says.
Others who have announced they will contest the mayoralty are: councillors Ray Ahipene-Mercer, Andy Foster, Rob Goulden, Alan Probert and Celia Wade Brown, and businessman Jack Yan.