The final results of the flag referendum are in, confirming Kyle Lockwood's Silver Fern the winner.

This is consistent with the preliminary results released on Friday night.

The official results includes tens of thousands more votes date-stamped before voting closed on Friday and received by the Electoral Commission by noon today.

The black, white, and blue flag will go up against the current New Zealand flag in a run-off next March.

In the preliminary results it only narrowly pipped the former Wellington designer’s alternative Silver Fern design, a mere 14,000 votes ahead of its Red, White and Blue sister for a 50.53 percent to 49.47 percent victory.

Critics of the referendum have pointed to the 48 per cent voting turnout as a sign of dissatisfaction with the process.

The high level of ‘informal’ votes, at nearly 10 percent on the back of a campaign to spoil ballots in protest, has also been highlighted by some.

However, Prime Minister John Key, who has led the charge for a new flag, said on Saturday he was happy with the voting levels and “delighted” with New Zealand’s choice of alternative.

“It was my number one choice but I also think we'll have a real contest now. You’ve got a flag which in a lot of ways is similar to our current flag but also embodies the silver fern.”

- Stuff