South Islanders were slightly ahead of the north for income levels -- scoring a 4.0 compared to 3.3 for the north.
That's despite not being quite as well educated as North Islanders -- which scored 6.8 for education, compared to 6.7 for Mainlanders.
The two islands were equal on "access to services", with a score of 8.3, and environment, where both scored a perfect 10.
Deputy Mayor of Auckland Penny Hulse said she could see the advantages of both islands: "For me Auckland will always be best ? our harbours and beaches and maunga and our diversity -- but why wouldn't you be filled with joy living somewhere as beautiful as the South Island."
The report compared 362 regions in 34 countries, based on national statistics provided to the OECD.
The scores for both islands ranked similar to Queensland, Northern Norway, North Middle Sweden and Prince Edward Island in Canada.
While the report didn't name an overall top-ranked region, the Australian Capital Territory ranked scores above 8.5 for every category, and scored four scores of 10.0 in income, civic engagement, safety and health.
The report found that while 15 American states and the Australian Capital Territory scored 10 in income, the American stats also had low scores in safety, health or environment.
South Island:
Income 4.0
Environment 10.0
Jobs 9.4
Education 6.7
Civic Engagement 7.2
Access to Services 8.3
Housing 7.5
Safety 9.5
Health 7.8
North Island:
Income 3.3
Environment 10.0
Jobs 7.6
Education 6.8
Civic Engagement 6.7
Access to Services 8.3
Housing 7.0
Safety 9.4
Health 7.5
North Island and South Island results similar to:
Northern Norway, Queensland, Prince Edward Island (Canada), North Middle Sweden and Western Finland.
Five best ranking regions:
Australian Capital Territory
Western Australia
New Hampshire (USA)
Queensland
New South Wales