Waiheke Island and Rodney residents will learn today whether their bid to break away from Auckland Council has succeeded.
The Local Government Commission is due to announce its decision today.
If successful, it could carve off about a quarter of the super city's landmass.
The Our Waiheke group has been campaigning to have a unitary council, arguing issues on mainland Auckland have limited relevance on Waiheke Island.
After a petition to separate from Auckland City Council, a referendum was held in 1991. The vote failed and Waiheke stayed part of Auckland City.