One of those flags, known as the Silver Fern (Black, White and Blue) design, is a leading contender to compete against the existing national flag and has been endorsed by the Prime Minister.
The name behind those flags is Kyle Lockwood, a Wellington-born architectural technologist living in Melbourne.
"I can't believe five of them made the list," he told the Herald this week.
He admits his designs - an identical template with different colours - were purely a drawing exercise.
The first seed of his flag design came when he enrolled in the army after leaving high school and wore the silver fern on his blue beret.
The national flag flew over the Burnham Military Base in Christchurch where he was based, but he "actually felt more proud of the fern on my hat".
His father represented New Zealand in underwater hockey, which used the fern as its emblem.
Later, at Massey University, Kyle Lockwood did a rough sketch of the flag during an architecture lecture.
That sketch was filed away for four years, until he returned to it for a competition run by the local newspaper Hutt News in 2004.
When he won that competition, he got a call from British flag expert Graham Bartram, who gave him some tips to make the flag better.
The silver fern, he says, is a symbol of multiculturalism because of its many fronds joined by a stem, the Southern Cross is a tribute to the existing flag, and the stars are the island groups - North, South, Stewart and Chatham islands. The blue hints at the Pacific Ocean and the red is a distinctive Maori colour as well as a mark of sacrifice during wartime.