Last year, the taxman was left sitting on a pot of $180 million in overpaid tax. So why aren't Kiwis filing tax returns to get their money back?
EnableMe director Hannah McQueen joined The AM Show on Monday to discuss how it's done.
"A lot of us don't realise it's our money because we think that our payroll system is deducting the right amount of tax," she says.
"And in most instances it is but it's assuming you've worked at that income level for the whole 12 months."
While some companies have sprung up to do it for you, they charge a hefty commission. Ms McQueen says it is "very easy" to do it yourself.
"It will take five minutes of your time to do it," she told host Duncan Garner.
"You go to the IRD website, then you just click a button that does a calculation as to whether you're due a refund.
"You just type in your total annual income, and it will say you should have paid this amount of tax. You compare that to your payslip, which says this is how much tax you have paid, and if there's a difference then you press the button to get the tax refund."
But if you have underpaid - there's not need to worry.
"Don't press any button and just back away from the computer," she says.
"You're not obliged to pay any shortfall if you're salaried."
Ms McQeen encourages Kiwis to get their money back, as even a little bit can make a huge difference many people.
"I think most of us are living payday to payday, whether we're doing that by choice or not," she told Garner.
"Any little bit of extra money is helpful."
Watch the full interview above.
The AM Show with Duncan Garner, Amanda Gillies and Mark Richardson, weekdays 6-9am on RadioLIVE and streaming live to the rova app on Android and iPhone.