Sir John Key says if he could go back and be Prime Minister again he would not hold the flag referendum that was heavily criticised and proved costly.
He said he would instead simply change the flag without any public consultation.
"I think it's one of those things that all hell would have broken loose for a couple of months, then we would have worn it, gotten used to it and been proud of it," he told 66 Magazine’s latest edition.
Two flag referendums were held in 2015 and 2016 and cost the Government $26 million.
The former Prime Minister was strongly in favour of changing the national flag to a black and white silver fern design.
Fifty-six per cent of Kiwis choose to keep the flag with its British Union Jack and 43.2 per cent were in favour of the new design, which was selected following an earlier vote.
The current chairman of ANZ Bank told the 66 Magazine still believed New Zealand should change its flag.
"I still believe that, as a small country at the bottom of the world if we want people to know us, we need a symbol that is ours," he says.