GST Return Calculator NZ

This calculator works out how much GST you need to pay, or will be refunded, on your New Zealand GST return, from your total sales and total expenses. GST works as a tax on the value you add: you collect 15 percent GST on your sales, the output tax, and you can claim back the GST you paid on your business expenses, the input tax. What you owe Inland Revenue, or what they owe you, is the difference between the two. Many small business owners find the GST return stressful simply because they are unsure of the figure, but the arithmetic is straightforward once you know your GST-inclusive sales and expenses. This tool does it for you. You enter your total sales including GST and your total GST-inclusive expenses for the period, and the calculator works out the GST collected on your sales, the GST you can claim on your expenses, and the net amount to pay or be refunded. The results update as you type. Use it to estimate your GST bill before filing, to set aside the right amount through the period, or to check a return. The GST content of a GST-inclusive amount is three twenty-thirds of it, the standard way to extract 15 percent GST from a tax-inclusive figure. If the GST on your sales exceeds the GST on your expenses, you pay the difference; if your expenses carried more GST, perhaps because you made a large purchase or had a quiet sales period, you receive a refund. A good habit is to set aside the GST portion of each sale as it comes in, so the money is there when the return falls due. This calculator covers the common case where all sales and expenses are standard-rated; zero-rated and exempt supplies, and adjustments, are handled separately.

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$9,000 to pay
GST to pay or refund
GST on sales$15,000
GST on expenses$6,000
StatusPay IRD

GST = amount x 3/23. Net = GST on sales - GST on expenses. Positive means pay IRD; negative means a refund. Covers standard-rated supplies; zero-rated and adjustments are separate.

How it works

The GST collected on your sales is the GST-inclusive sales figure times three twenty-thirds, the way to find 15 percent GST within a tax-inclusive amount. The GST you can claim on expenses is found the same way. The net GST is the GST on sales minus the GST on expenses: a positive figure is payable to Inland Revenue, a negative figure is a refund.

Worked example

With GST-inclusive sales of $115,000, the GST collected is $115,000 times 3 over 23, which is $15,000. On GST-inclusive expenses of $46,000, the GST to claim is $46,000 times 3 over 23, which is $6,000. The net GST is $15,000 minus $6,000, so $9,000 is payable to Inland Revenue.

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Data sources: the rates and thresholds on this page are maintained against Inland Revenue. Figures are checked twice monthly.