Mixed-Use Holiday Home Apportionment Calculator

The Mixed-Use Holiday Home Apportionment Calculator helps New Zealand owners split the running costs of a holiday home between income-earning use and private use, so they can work out the deductible portion for tax. Under the mixed-use asset rules, a holiday home that is rented out at times, used privately at times, and left empty for 62 days or more in the year, must have its expenses apportioned rather than fully claimed. The standard formula divides income-earning days by the total days the property was actually used, that is rented days plus private days, and ignores the days it sat empty. You enter the number of days the home earned income, the number of days it was used privately, and the total expenses for the year such as rates, insurance, interest, and repairs, and the tool returns both the deductible percentage and the deductible dollar amount. Holiday home owners, bach owners, and their accountants use it to size the deduction before filing and to test how more rental nights would change the claim. A few tips make the result reliable. Count only genuine income-earning days when the home was rented at market rates, and treat days used by family or at mates rates as private. Keep a simple diary of who used the property and when, because the day counts drive everything. Remember that days the home was unused and available do not count in this version of the formula, which keeps the split focused on actual use. The figure here is a planning estimate and not formal tax advice, but it turns a fiddly apportionment into a clear, defensible number you can take to your accountant.

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$7,200
Deductible expenses
Deductible percentage60.0%
Total used days100

Deductible % = income days / (income days + private days). Deductible $ = expenses x that %. Estimate only, not financial or tax advice.

How it works

The tool adds your income-earning days and private days to get the total used days, then divides income days by that total to find the deductible percentage. It multiplies your total expenses by that percentage to give the deductible dollar amount. Empty days are not counted.

Worked example

With 60 income-earning days and 40 private days, total used days are 100, so the deductible percentage is 60 divided by 100, which is 60.0 percent. Applying that to $12,000 of expenses gives a deductible portion of $7,200.

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Frequently asked questions

What counts as an income-earning day?

It is a day the property was rented out to earn income at market rates. Days used by family, friends, or yourself, or let at mates rates, count as private rather than income earning.

Why are empty days ignored?

This apportionment splits expenses by actual use, so it divides income days by income days plus private days. Days the home sat empty are left out of this particular formula, which keeps the ratio based on how the property was really used.

Which expenses can I include?

Include the running costs of the property such as rates, insurance, interest, and repairs and maintenance for the year. The calculator then applies the use ratio to give you the deductible portion.