Just over three million voting packs were sent out as part of the $26 million flag referendum process.
Voting closes on Friday, but papers need to be in the post by Tuesday to be counted.
Labour leader Andrew Little said the return rate seemed pretty consistent with other referendums New Zealand had held in the past.
But he questioned how many votes would be returned invalid.
“I know that plenty of people in organisations are saying they are organising campaigns of invalid vote returns. So we would have to see how high that is compared to other referendums to see if people are genuinely interested in a change of flag.”
It was no secret that Labour had wanted to change the flag since about 1972 but he did not believe the country would have a new flag next year.
“It’s always a question about timing and people have to be ready for it and most importantly a case for change has to be made and a case for change has never been made.”
Voters have been asked to rank five new flag designs they would prefer if the current flag was to be replaced.
That includes a last minute addition of the Red Peak design after a social media campaign and petition.
Act leader David Seymour, who is in favour of Red Peak, expected the number of returned votes to climb nearer the deadline.
“Look it’s a low turnout but any teacher who has ever set an assignment knows that most people leave most things to the last minute.
“I hope that people will be able to get their votes in before the deadline but they are going to have to be pretty quick,” he said.
Wellington resident Frances Porter had sent her papers in but she was not at all surprised others had not.
“People still are ramped up, as it were, about Gallipoli and world wars and fighting under that flag and then we choose to do [the referendum] just before Christmas.”
The Electoral Commission said it was not drawing conclusions or making any predictions at this point.
It said 1,064,645 people had voted so far and the commission would release an updated figure today.
The winning design will go up against the current flag in a second referendum in March.