Census 2018: Nine things you need to know about tonight's Census

More than 1,200,000 Kiwis have filled in their Census forms online in a data-gathering exercise that will help give a snapshot of New Zealand's population and general needs.

Census Day is today, March 6, and the vast majority of people were doing it online this year, Stats NZ senior media adviser James Weir said.

"The managers of the Census are please with how it is going so far."

Stats NZ wanted 70 per cent of all Census forms filled in online, but anyone can ask for a paper form instead.

The data-gathering outfit has everything you need to know below.

To complete your Census you will need:

• Your access code letter

• Around 20 minutes to complete the Census, individual forms take about eight minutes.

• Everyone in your household to take part

What is the importance of the Census?

Census information will help determine how billions of dollars of Government spending is spent, it also can be used to inform decisions and make plans about services.

This can help identify where hospitals, schools roads and public transport is needed.

Is the Census compulsory and can I get fined if I don't complete it?

Yes. The Statistics Act 1975 requires everyone in New Zealand on Census day to take part, that includes tourists.

After Census day, any household that is yet to complete the Census forms will be contacted again by letter. Households that haven't completed the forms after these reminders will be visited by our field teams. If people still refuse to take part after these visits, then Stats NZ may consider prosecution.

Is anything new with this Census?

Stats NZ was asking everyone who had their access code letter and was able to take part online to do so.

Stats NZ was also asking new questions about mould and damp in your home, and has introduced a new set of disability questions.

What happens if I want to take part by paper/ hard copy?

Paper forms are available upon request. If you have your access code letter, you can call the helpline on 0800 CENSUS (0800 236 787) and they'll send out paper to you.

What happens if you've lost your access code?

If you've lost your code, a new one will soon be on its way to any household that hasn't responded by midnight tonight.

What happens if I am not at home?

Places like hospitals, residential homes, hotels and motels are treated a little differently from households. We deliver everything they need, including paper forms, closer to Census day, so that they can use them to count the people actually staying with them on Census night.

Are people yet to receive their Census?

The majority of the population has received their forms.

How long does it take to do?

2018 Census general manager Denise McGregor said "It doesn't take long to complete and timing for online forms is averaging four minutes for the dwelling form and eight minutes for the individual form."

For more information on how to fill out your Census form click here.