A political marketing expert says she believes many New Zealanders were turned off the idea of a new flag because the process felt forced.
Preliminary results show 1,200,003 votes were cast for the current flag, compared to 915,008 for the black and blue silver fern design.
Professor Jennifer Lees-Marshment says public engagement around the referendum could've been handled better.
"All the research shows -- I mean governments do this all the way around the world, it's not just New Zealand, it's not just the flag consideration project -- but they engage the public in a way that seems false because they don't show that connection between the input and the final decision."
Final results are expected on March 30, but it's unlikely the outcome will change.
The Electoral Commission says a total of 2,124, 507 voting forms were received -- a turnout of 67.3 percent of voters.
That makes it one of the most successful postal referendums in New Zealand history.