New research shows that people are underestimating how much they will spend in retirement on basics like groceries.
The survey also found that people are underestimating how much they can save for their retirement, especially if they start when they are young.
The Commission for Financial Capability asked people how much a retired couple might spend on groceries over 30 years.
Only eleven percent of people correctly guessed a couple would spend between $250,000 and $300,000.
The total bill of between $250,000 and $300,000 does not include alcohol.
Thirty years might seem like a very long time to be retired.
The Commission points out that we are living longer these days. A 65-year-old man can expect to live to 86-years-old and a woman can expect to live to 88.
But life expectancy is going up all the time. It's not unrealistic to expect a child today could live to 95.
The Commission's David Boyle says: "We're not suggesting anyone should stop enjoying themselves today, but work out a plan so you will be enjoying yourselves tomorrow as well. And the sooner you start putting a bit away, the greater the amount you will have to support you when you retire."
People were also asked how much they would have in their KiwiSaver account if they saved three percent of their income every year from 18 to 65. (This is based on the average income of $65,000 and the assumption they put the money into a Growth fund.)
The correct answer is between $300,000 and $400,000.
More than two thirds of people underestimated this, with nearly a third saying they thought the amount would be less than $100,000.
If they increased their savings rate from three percent to eight percent their savings would rise to between $600,000 and $800,000. Half of people surveyed expected it to be less than that.
The Commission for Financial Capability's David Boyle says: "If people realised how much they could end up with if they joined KiwiSaver and contributed regularly, then I think they would be much more likely to do so."
The theme of this year's Money Week is 'Show Me the Money' - showing how the costs of everyday items can add up over 30 years of retirement. So it is never too early to start planning.
The Commission has a range of tools for budgeting and saving and they can be found on its website.
More than 70 events are planned for Money Week. More information can be found here.