The head of Christchurch City Council's economic development agency is defending the cost of a new branding campaign saying that the Garden City tag may be past its use by date.

ChristchurchNZ has unveiled a new campaign and "Ōtautahi, Christchurch" logo, that pushes for a "new identity for the city" in a bid to attract more visitors and boost economic growth.

The revamp revealed during the week centres on a "city in pursuit of balance, where residents, visitors and workers have the space to make time for all types of play".

The agency was expected to contribute at least $100,000 on the half-a-million dollar project, with the remaining sum through the Ministry of Business, Innovation and Employment (MBIE).

Christchurch mayor Phil Mauger said there was a real buzz about the city.

"We are realising the investment of the past decade and taking our place as New Zealand's true second city where people can work, live, play and invest.

"There is so much right here for our residents, visitors and businesses - we've always had a strong connection to our environment and nature, now the town is buzzing and our new industries in tech, aerospace and manufacturing are really putting Christchurch on the map.

"This new city story gets that message out there to the country and the world."

ChristchurchNZ chief executive Ali Adams said the matter of marketing spend was something that sparked a range of views and was "subjective".

"You would notice very quickly if the money wasn't spent," she said.

"It can be seen as something that people have very strong opinions on and can be quite difficult to draw a direct line between the marketing and the economic impact that you absolutely notice when it's not there.

"And you really would notice in the post-Covid world if we weren't doing this," Adams said.

It would be detrimental if no money was spent on the city's branding, she said.

"It's that old chestnut of 50 percent of marketing is wasted.

"I just knew which one it is very difficult to work out exactly how much economic benefit you can contribute to marketing and to branding."

Between 4000-4500 resident surveys were completed with the agency engaging with thousands of visitors.

Some feedback they had received signalled that the "Garden City" nickname had become outdated, Adams said.

"They told us that the Garden City has a place in their hearts, but it was maybe a little bit out of date.

"So what we've done here is evolved that Garden City concept into a broader concept around balance.

"If you look back at the Garden City's origins, it was very much about the balance between humans and nature, and having the best of both worlds."

The look of the brand has been completed by some international consultants alongside a group of local agencies including design studio McCarthy, Kaupapa Māori studio Ariki Creative and local creative Tahu Robinson.

ChristchurchNZ said it would support businesses and residents to "understand and adopt" the identity.

A public event was scheduled for later this month before a series of promotional campaigns were launched.