GST Mixed-Use Asset Calculator

Mixed-Use Asset GST Rules in New Zealand

The mixed-use asset rules apply to assets valued at $50,000 or more that are used partly to earn income, partly for private purposes, and partly sit idle. The most common assets caught by these rules are holiday homes and baches rented on Airbnb or Bookabach, boats and yachts available for charter, and private aircraft. The rules are contained in Subpart DG of the Income Tax Act 2007 and apply equally for GST purposes.

The Key Concept: Idle Days are Excluded

The most important feature of the mixed-use asset rules is that idle days (days the asset is not used by anyone) are excluded from the apportionment calculation. Only days of actual use count. If your bach is rented for 30 days, used privately for 20 days, and sits empty for 315 days, the income-earning percentage is 30 / (30 + 20) = 60%, not 30 / 365 = 8.2%. This makes a dramatic difference to the GST input credits you can claim on expenses like rates, insurance, maintenance, and cleaning.

The 62-Day Safe Harbour

If the asset is rented for 62 or more days in the income year, the standard apportionment rules do not apply and you can instead use the actual use method. This can be more favourable for assets that are heavily rented. The 62-day test is assessed each year, so the method used can change from year to year as rental patterns change.

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Last updated: April 2026 | Rates current for the 2026/27 tax year