A major test of the Government's push to change the flag starts today, with the beginning of the first referendum.

Flag referendum voting papers will start to arrive in letterboxes across the country this morning.

Information about five flag options, including pictures and descriptions will be in voting packs and voters will be asked to rank the alternative flag options one to five in the order they prefer them.

All voting papers sent to enrolled electors should be delivered within the week and all people enrolled have until December 11th to vote.

Deputy Prime Minister Bill English expects there will be a good turn out, but he doesn't want to put a number on it.

"Some people have been a bit noisy about being against the whole idea but I've found increasingly people getting a bit serious about it. They start thinking well this is a real opportunity, there is a real opportunity - it's about New Zealand, it's not about the politics."

He believes it's a unique opportunity that New Zealanders should get actively involved with.

"Even if they don't want to change just incase it does change then it's good that they have a say about what's going to be there instead."

Chief Electoral Officer Robert Peden explained voters are being asked to rank the alternative flag options one to five in the order they prefer.

"You mark the paper by putting a one under the flag you most prefer and then you can put a two next to your next preferred option if you wish, and you can rank as many or as few flag options as you want from one to five," he said.

"We'll be sending out 3.1 million voting papers, that's over 92% of people eligible to enrol have registered."

The official result of the first referendum will be announced on December 15th then, in March next year, there will be another referendum to choose between the most preferred option and the current flag.