Retailers in Auckland are leaving their shops over steep rental, while a new luxury shopping hub is emerging, according to a study by an expert.

The study, released by Chris Dibble, Jones Lang LaSalle's research and consulting associate director, was done over observations that the Auckland retail spot has become squeezed with no prime space left.

While landlords had been unwavering in their negotiations with tenants, retailers Zambesi, World, and Kate Sylvester were leaving High St. after about two decades and moving to Britomart.

A spokesperson for developers Cooper & Company said 19 new shops opened last year in Britomart, an emerging hub for retailers and shoppers.

Mr Dibble said in his study that there are indications that more stores are considering moving from High St.

In 2011, Zambesi boss Neville Findlay blamed rising rents for the move, and said the opportunity to build a new flagship store in Tyler St was just too tempting to keep the High St shop, the New Zealand Herald reported.

Mr Dibble attributed the retailers move to Auckland Council's completion of the streetscape upgrade along Fort St and Fort Lane.

"The move of High St retailers to Britomart, and the Imperial Buildings' transformation of under-utilised space into chic upscale retail, is another example of what savvy landlords are doing to compete for first-rate retailers in a tough trading environment."

Mr Dibble also noted that confidence in the retail sector had dropped slightly, but the Auckland CBD retail vacancy rate decreased from 5 per cent in June to 4.5 per cent last month.

"Positivism should be evident, with trend data from Statistics NZ showing a general uplift in consumer spending. While indications [are that] overall retailer demand and supply is sufficiently balanced, prime premises continue to receive healthy levels of inquiry.

"The Britomart continues to be the centre for new development and upscale retail, with new premises opening in Commerce St. The Imperial Buildings at Lower Queen St also provide new chic retail space. This is a major gain for Britomart, but a major loss for High St."

Mr Dibble pointed out that the rising rentals were caused by the lack of suitable prime CBD space, unwavering landlords and a tenant flight to quality.

Upper Auckland prime rents rose by 4.5 per cent last year. Average prime Auckland net face retail rents are around $1,900/sq m, up 2.7 per cent, according to the Herald.

Prime premises typically range from 40sq m to 250sq m, depending on store type, so tenants in bigger shops are believed to be renting at $475,000 annually, while boutiques pay $70,000 to $80,000.