Flag vote to use preferential system

Next month voters will be asked to rank their alternative flag options from 1 to 5 in order of preference. FILE PHOTO

The voting for the favourite flag out of five will be done by the Single Transferable Vote system, the same system used in Wellington to elect their mayor.

Next month voters will be asked to rank their alternative flag options from 1 to 5 in order of preference.

In other words, "1" indicates the flag most preferred, and "2" is the next most preferred.

In 2010 Wellington mayor Kerry Prendergast described STV as "unfair and undemocratic" after it went down to the wire - mathematically - between her and challenger Celia Wade-Brown.

Ms Prendergast said she would have retained her mayoralty under First Past the Post, but lost to Ms Wade-Brown under STV.

STV works by eliminating the least preferred candidates round by round, with their votes being transferred to each voter's next most favoured candidate.

Masterton District Council uses a First Past the Post system for local body elections.

Voters for the flag will be asked: If the New Zealand flag changes, which flag would you prefer?

The referendum will run from November 20 to December 11.

Only those who are enrolled to vote can vote in the referendum.