Deceased Estate Tax Obligations: Australia and New Zealand Cross-Border Filing

Two Tax Jurisdictions, One Estate

When an Australian citizen or resident dies in New Zealand, the executor may face tax obligations in Australia and, depending on the deceased's assets and income, in New Zealand. The Australian Taxation Office (ATO) requires a final individual tax return for the deceased, covering income earned from 1 July of the current financial year up to the date of death. If the estate continues to earn income during the administration period — rental income, dividends, interest — the ATO also requires a separate trust tax return for the deceased estate.

On the New Zealand side, Inland Revenue (IRD) has its own requirements if the deceased held New Zealand assets or earned New Zealand-sourced income. Even Australian tourists who die during a short visit can generate a New Zealand tax obligation if they held NZ bank accounts, KiwiSaver funds, or property.

These cross-border filing obligations catch many executors off guard, particularly when they are already dealing with the emotional and logistical weight of a cross-border death.

The ATO Final Tax Return

The executor (or the deceased's tax agent) must lodge a final individual tax return with the ATO. This covers:

• Employment and business income up to the date of death
• Investment income — dividends, interest, rental income — earned before death
• Capital gains or losses triggered by the death (more on this below)

The due date depends on when the person died and whether a registered tax agent is lodging, so confirm the deadline with the ATO or tax agent. If the deceased owed a tax debt, it becomes a debt of the estate. If they were owed a refund, it is paid to the estate.

One catch that applies specifically to overseas deaths: if the deceased was receiving income from both countries, the executor needs to determine tax residency status at the date of death. An Australian retiree living permanently in New Zealand may have become a New Zealand tax resident, which changes which country has primary taxing rights and how the double tax agreement applies.

Capital Gains Tax — Australia's Hidden Sting

New Zealand does not impose a general capital gains tax. Australia does. This asymmetry creates a specific trap for cross-border estates.

When an Australian asset — investment property, shares, managed fund units — passes from the deceased to a beneficiary, the transfer is generally CGT-exempt at the point of death (the beneficiary inherits the deceased's cost base). But when the beneficiary eventually sells the asset, they pay CGT on the gain calculated from the deceased's original acquisition cost, not the market value at death.

The trap gets sharper when a New Zealand resident is the beneficiary. If a non-resident of Australia inherits Australian real property and later sells it, Australian CGT and foreign-resident rules apply; those rules can limit or remove the 50% CGT discount, depending on the asset and relevant dates. The effective tax rate on a long-held property can be substantial.

The Trust Residency Trap

This is the scenario that generates the largest unexpected tax bills in trans-Tasman estates. If the deceased established a family trust in New Zealand and the appointed successor trustee is an Australian resident — say, an adult child living in Sydney — the trust may be deemed an Australian resident trust for tax purposes under the Income Tax Assessment Act.

The consequences are severe. An Australian-resident trust is taxed on its worldwide income by the ATO, including income from New Zealand assets that was previously only subject to New Zealand tax. The trust may also face retrospective CGT exposure on assets it has held for years.

Trust residency is fact-specific, so do not assume that appointing a New Zealand-resident trustee or co-trustee automatically preserves NZ tax residency. Get trans-Tasman tax advice before changing the trustee or allowing an Australian-resident successor to take control; unwinding a changed residency position may create further tax consequences.

The Double Tax Agreement

Australia and New Zealand have a comprehensive double tax agreement (DTA) that prevents the same income from being fully taxed in both countries. The DTA allocates taxing rights depending on the type of income and the residency of the taxpayer. For a deceased estate, the executor or accountant must identify the relevant DTA article for each income type and claim any applicable foreign income tax offset or other relief on the ATO return. Do not rely on a single withholding rate or assume that the same treatment applies to salary, pensions, rent, interest, and dividends.

IRD Obligations in New Zealand

If the deceased held New Zealand assets or earned New Zealand-sourced income, the executor may also have to deal with IRD. This is straightforward for simple estates — IRD's online system accepts returns for deceased persons, and the process is well documented on their website. The IRD also needs to be notified of the death so that any tax refunds or liabilities can be directed to the estate rather than the deceased's personal tax account.

For notification, you can use myTrove (New Zealand's death notification service) to notify IRD and other NZ agencies simultaneously. Note that myTrove does not cross the border — it cannot notify Australian agencies.

Getting Professional Help

Cross-border estate tax is specialist territory. A standard suburban accountant who handles annual returns is unlikely to have experience with the DTA, foreign income tax offsets, trust residency rules, and the interaction between the Australian Income Tax Assessment Act and New Zealand's Income Tax Act. Engage a certified public accountant or chartered accountant who specialises in trans-Tasman tax — your estate solicitor can usually recommend one.

Our Australian Dies in New Zealand emergency guide includes the complete financial administration sequence — from superannuation claims and bank notifications through to tax filing — so you can coordinate every obligation without missing critical deadlines.