But attempts by former Vero chief executive Roger Bell and Richard Conway to launch a site in New Zealand have failed because New Zealand's main insurers are not willing to share their information.
A message on the site iCompare reads: "The major insurers operating in this country have refused to work with us to allow Kiwis to make convenient and accurate comparisons of insurers' terms and conditions, denying Kiwis the benefits enjoyed by consumers in many countries overseas."
Conway said there was interest from smaller insurance companies and some from overseas.
David Naulls of Consumer NZ said the lack of a comparison site in New Zealand was bad news.
Conway said he was sure New Zealanders were paying more for insurance because of the absence of a comparison site. But Insurance Council chief executive Tim Grafton said the sites encouraged people to look at price without considering the cover.
An IAG spokesman said: "Comparison sites [cut] out the crucial element of providing a feedback mechanism between insurer and customer that can help secure the most appropriate type of cover."