"Kiwis have had an opportunity to really consider what our flag means, what it represents to them, and for the first time in history, choose a flag," Professor Burrows said.
He said he was pleased with the turnout in the second referendum - higher than all but one postal referendum.
Kyle Lockwood, the designer of the defeated silver fern flag, said he was "ecstatic" despite the outcome.
Polls had initially predicted 30 per cent support for his flag - far lower than the official result, he said.
"I think it has created a platform for another vote in future, but I don't know when that will be," he said.
The Melbourne-based New Zealander said he was looking forward to a break after six months in the spotlight.
Prime Minister John Key, who backed a flag change, is in Washington for a nuclear summit. He said last week that the Government would not revisit the flag issue under his leadership.
New Zealand First leader Winston Peters said the flag referendum had distracted attention from "real and genuine" constitutional issues, such as a written constitution, the length of the parliamentary term, and the role of the Treaty of Waitangi.
Gun-toting kiwis among rejects
Gun-toting kiwis, chocolate fish, obese kittens and Nazi symbols were among flag designs rejected early in the referendum process.
While some zany designs made the cut - most notably the laser kiwi - another 2700 were rejected for not meeting the required criteria.
The Department of Prime Minister and Cabinet said the discarded designs either used sources without citation, incorporated words, faces or complex objects, or were considered offensive or divisive.
Most of the rejected submissions featured the existing national flag.
Many of them included Prime Minister John Key - sporting a ponytail, poking his tongue out, making a thumbs-up or transformed into a lizard.
Food was also a common theme, with meat pies, sausages, kiwifruit and lattes featuring on some of the discarded flags.
Among those deemed too offensive were swastikas, lewd pictures and phallic designs.
A total of 10,200 public submissions passed the first hurdle, and were whittled down to a longlist of 40 and a shortlist of five.