Posted Overseas with DFAT? Your Super Scheme Decides Almost Everything

Two Canberra public servants accept overseas postings in the same month. One is a contributing member of CSS or PSS. The other joined more recently and is in PSSap. They have the same salary, the same house in Canberra and the same questions — and their tax outcomes are almost entirely different.

That is not a quirk. It is written into the residency rules, and the Australian Taxation Office uses a DFAT officer as its own worked example.

The rule almost nobody mentions

The ATO has a residency test that exists specifically for people in this situation. It is called the superannuation test, and it works like this: if you are a contributing member of the Public Sector Superannuation Scheme (PSS) or the Commonwealth Superannuation Scheme (CSS), you are an Australian resident for tax purposes — full stop, regardless of where you live or for how long.

The ATO says the test “was designed to ensure that Australian government employees working at Australian posts abroad (such as diplomats and officials of the Department of Foreign Affairs and Trade), and their spouses and children under 16 years old, were treated as Australian residents”.

The ATO’s own example is a DFAT officer posted to Thailand for three years who is a CSS member. She remains an Australian resident.

The test does not apply to PSSap. CSS and PSS are closed to new members, so in practice this splits along the line of when you joined.

Source: ATO, “Residency – the superannuation test”, last updated 3 June 2026.

Your spouse’s residency is decided by your super scheme too

This is the question we are asked most often, and the answer surprises people.

If you are an Australian resident under the superannuation test, the ATO treats your spouse and any children under 16 as Australian residents as well. Not “probably”. Not “if they keep ties here”. Automatically, because you are.

“Spouse” is defined broadly: a person of any sex in a relationship registered under a state or territory law, or someone who lives with you on a genuine domestic basis as a couple without being married to you.

If you are in PSSap, none of that applies. Your partner’s residency is worked out on their own facts under the ordinary tests — where they live, what ties they keep, how long they are away. Two people in the same household can end up on different footings.

Source: ATO, “Residency – the superannuation test”, last updated 3 June 2026.

What actually changes if you do become a foreign resident

If the superannuation test does not cover you and you become a foreign resident, the tax-free threshold disappears. You are taxed from the first dollar.

On a taxable income of $120,000, an Australian resident pays $26,788 in tax plus $2,400 Medicare levy — $29,188. A foreign resident pays 30% of the lot: $36,000, with no Medicare levy. Roughly $6,800 more, before any credit for tax paid overseas.

Source: ATO, “Tax rates – Australian resident” and “Tax rates – foreign resident”. Both columns show 2025-26 because the ATO has not yet published a 2026-27 foreign-resident rate; setting 2026-27 resident rates against 2025-26 foreign-resident rates would not be a like-for-like comparison.

The Canberra house: renting it out

Rental income is assessable whether you are a resident or not. The exposure is what happens when you eventually sell.

Since 1 July 2020, a foreign resident cannot claim the main residence exemption at all. The ATO is blunt about it: if you are a foreign resident when you dispose of the property and you do not meet the narrow life events test, you are not entitled to the exemption “even if you were a resident for some of the ownership period” — and you get no partial or apportioned exemption either.

That means capital gains tax on the entire ownership period, not the years you were away.

The same page says: “If you’re an Australian resident at the time you dispose of your property, this doesn’t affect you.”

So the CSS or PSS officer, who never stops being a resident, is untouched. The PSSap colleague on the identical posting may not be.

Source: ATO, “Main residence exemption for foreign residents”, last updated 22 June 2026.

The Canberra house: leaving it empty

If you do not rent it out, the position is better — and this is worth knowing before you decide.

The ATO lets you keep treating a former home as your main residence for up to six years if you produce income from it, such as rent, or indefinitely if you do not. Leaving it empty removes the six-year clock entirely.

Two conditions apply. It must have been your main residence first — you cannot apply the exemption to a period before you actually lived there. And you cannot treat any other property as your main residence at the same time, apart from a six-month overlap when moving.

But read this together with the section above. Leaving the house empty preserves the absence rule; it does not preserve the exemption if you are a foreign resident on the day you sell. Both things have to be true.

Source: ATO, “Treating former home as main residence”, last updated 22 June 2026.

Your shares: the trap is leaving, not investing

You can keep investing in Australia. The problem is the moment your residency changes.

When you stop being an Australian resident for tax purposes, the ATO treats you as having disposed of your CGT assets at their market value on that day — everything except taxable Australian property. It is called deemed disposal. You have sold nothing and received nothing, and there can still be a capital gain to declare.

There is a second sting: if you acquired an asset after 8 May 2012 and sell it once you are a foreign resident, the full 50% CGT discount is not available. You may get an apportioned discount for the period you were a resident.

The other side of the coin: once you are a foreign resident, Australia taxes you only on taxable Australian property — real property and interests in it. Listed shares are not on that list.

Source: ATO, “How changing residency affects CGT” and “Taxable Australian property”, last updated 22 June 2026.

If you have just bought your first home in the ACT

This one catches younger officers, and the timing is unforgiving.

The ACT Home Buyer Concession Scheme requires that at least one buyer owns and lives in the home as their principal place of residence continuously for a minimum of one year, starting within one year of settlement. Miss it and you are liable for full conveyance duty on the transaction, and the ACT Revenue Office says penalty tax or interest may apply as well.

There is an exemption. The Commissioner for ACT Revenue can reduce the residence period or extend the start date — but only where there has been “an unforeseen circumstance such as a health-related issue”, and only if you ask within 18 months of settlement.

A posting you applied for and accepted may not be unforeseen. That is a conversation to have before you sign, not after.

Note the wording is “at least one buyer”. If one partner remains in the home, the requirement may still be met.

Source: ACT Revenue Office, “About the Home Buyer Concession Scheme”. “First home buyer grant” can mean the ACT concession, the federal Australian Government 5% Deposit Scheme (formerly the Home Guarantee Scheme), or the First Home Super Saver Scheme. The conditions differ.

What to do with this

Find out which scheme you are in before anything else. It is the single fact that determines your residency, your spouse’s residency, what happens to your house, and whether leaving triggers a tax event on your share portfolio.

If you are in CSS or PSS and still contributing, most of the risks above do not reach you. If you are in PSSap, all of them are live, and the order in which you do things — when you sell, when you rent, when you leave — starts to matter a great deal.

None of this is advice about your situation. It is the shape of the problem. What it means for you depends on your scheme, your property, your partner’s circumstances and the length of the posting.

Frequently asked questions

Does taking an overseas posting make me a non-resident for tax?

Not if you are a contributing member of CSS or PSS. The ATO’s superannuation test treats you as an Australian resident regardless of where you live. If you are in PSSap the test does not apply and your residency is worked out on the ordinary tests.

Is my spouse a resident or a non-resident?

If you are an Australian resident under the superannuation test, your spouse and any children under 16 are Australian residents too. If you are in PSSap, your spouse’s residency is assessed on their own circumstances.

If I rent out my Canberra home while posted, do I pay more tax?

The rent is assessable either way. The larger issue is capital gains tax on sale: a foreign resident loses the main residence exemption entirely for property sold after 30 June 2020, with no apportionment.

What if I leave the house empty instead?

You can treat a former home as your main residence indefinitely if you do not produce income from it, rather than the six years that applies if you rent it out. It must have been your main residence first.

Can I keep my Australian shares while I am overseas?

Yes. But if you stop being an Australian tax resident you are treated as having disposed of those shares at market value on that day, which can create a capital gain without a sale.

Does an overseas posting affect the ACT first home buyer concession?

It can. The scheme requires at least one buyer to live in the home continuously for a year, starting within a year of settlement. The Commissioner can waive it only for unforeseen circumstances, and an accepted posting may not qualify.