Spouse Details on Your Tax Return: Every Place They Change Your Tax

Spouse Details on Your Tax Return: Every Place They Change Your Tax (2025–26)

Australian individual tax return, 2025–26 (year ending 30 June 2026). General information only — not personal tax advice. Last reviewed: June 2026.

Most people treat the spouse section as a formality — a name, a date of birth, an income figure. In reality, your spouse's details quietly drive at least eight separate calculations on your return, and a wrong or missing figure can flip your Medicare levy surcharge, your private health rebate, and several offsets. This guide maps every place spouse data flows, how the surcharge is split if you couple up or separate mid-year, and the rule that surprises everyone: the ATO can't tell you your own spouse's income.

When do you have to include spouse details?

You complete the Spouse details (married or de facto) section if you had a spouse at any time during the income year. If you had more than one spouse, you use the details of your last spouse for the year. If the relationship didn't run the full year — you married, separated, or your spouse died — you enter the dates you had a spouse.

The section captures your spouse's name, date of birth, gender, the period they were your spouse, whether they died during the year, and a set of income labels — most importantly their taxable income (Label O), plus reportable fringe benefits, reportable super contributions, net financial-investment and rental losses, child support paid, and two pension labels (P and Q) used for SAPTO.

Where spouse income actually hits your return

Spouse data isn't one calculation — it's a thread running through the whole assessment. Here's the full map.

Does my spouse's income affect my tax? A quick yes/no

It's one of the most asked questions — and the answer is "it depends which part of your tax you mean." Spouse income changes the income-tested items, but never your own rates or loan repayments.

How do you find out your spouse's income?

This is the question that trips up separated and privacy-conscious couples — and the answer has a hard edge. You're required to seek the figures from your spouse, whether or not they need to lodge a return. The usual sources are their tax return or notice of assessment, their income statement / PAYG summary, and any trust distribution statements. Child support paid is on record with Services Australia.

So what happens if you genuinely can't obtain an exact figure — a hostile separation, an uncontactable ex, a spouse who refuses? The ATO's position is practical:

One prefill nuance: if you had a spouse on 30 June last year, myTax may pre-fill your spouse's name and date of birth from your prior-year return — but it will never pre-fill their income. That figure is always something you obtain or reasonably estimate.

What counts as spouse income?

A common misconception is that "spouse income" means just their salary. For the income-tested items, it's the broader income for surcharge purposes — so a spouse with modest taxable income but salary packaging or investment losses can still push the family figure up.

The losses are added back — meaning negative gearing reduces taxable income but not the figure used for the surcharge and rebate tests.

The Medicare levy surcharge — the biggest spouse-driven number

Having a spouse moves you from the single threshold to the (higher) family threshold, but it also means the ATO combines both incomes to test it. For 2025–26:

*Family threshold increases by $1,500 for each dependent child after the first.

Two spouse-specific quirks matter:

How the surcharge is split if you couple up or separate during the year

This is where it gets misunderstood. When your relationship status changes mid-year, the surcharge isn't all-or-nothing — it's worked out on a days basis, and the threshold that applies changes depending on the period:

*Plus $1,500 per dependent child after the first. For the coupled days, the test uses your own income against the family threshold — not the combined figure. The rate tier is set by your circumstances on 30 June.

The mirror image applies if you marry or partner up during the year and are together on 30 June: the family thresholds apply on a daily basis from the date you became a couple, the single threshold covers the earlier single days, and your status on 30 June (now a couple) determines the rate tier.

When one spouse is exempt from the Medicare levy (Defence, DVA, blind pension)

Some people are exempt from the 2% Medicare levy because they're a prescribed person — most commonly a Defence Force member entitled to free medical treatment, a full-time Defence reservist, a DVA Gold Card holder, or a blind pensioner. But the exemption isn't automatic when there's a family: it's full or half, depending on who covers the dependants.

The family agreement — and why the lower earner usually signs it

Where both partners are prescribed persons (say, both Defence Force members) and they have dependent children, the children still need to be covered — so one partner must carry a half levy for them. The couple decide who, in a written family agreement. Because the half levy is a percentage of that person's income, it's almost always cheaper for the lower-income partner to take it on.

Three life events, three different rules

Married or partnered during the year Part-year

Separated during the year Part-year

Spouse died during the year Special rule

SAPTO and your spouse (Item T1)

If you (or your spouse) have reached Age Pension age and are on a modest income, the Seniors and Pensioners Tax Offset interacts with your spouse in two ways: a combined-income eligibility gate, and a transfer of unused SAPTO between partners. Maximum amounts and thresholds for 2025–26:

The two-step quirk: eligibility is first tested on combined rebate income, but the offset is then calculated on your individual rebate income — so you can pass the couple gate yet receive nil because your own income exceeds half the combined threshold. SAPTO reduces by 12.5 cents for every dollar of rebate income above the shade-out threshold.

Invalid and invalid carer offset (Item T5)

If you maintain an invalid spouse — or a carer of an invalid family member — you may be entitled to this offset, worth up to $3,396 for 2025–26. The eligibility test depends on who the invalid is:

So for the most common case — an invalid spouse — it's tested on your own adjusted taxable income, not the combined figure. Separately, the dependant's own ATI reduces the offset, cutting it out once their ATI reaches about $13,866. One more gate: if you or your spouse are eligible for Family Tax Benefit Part B for the full year, you can't claim this offset.

Spouse super contribution offset (Item T3)

If you contribute to the super of a low-income spouse, you may claim a tax offset of 18% of contributions up to a $3,000 ceiling — a maximum of $540. The full offset is available where the spouse earns $37,000 or less, sliding to nil at $40,000. It draws on the spouse income you've already entered in the spouse section.

Other husband-and-wife tax nuances

A couple can only have one main residence at a time (CGT)

For the capital gains tax main residence exemption, a married or de facto couple can generally only treat one home as their main residence at any time. If you each nominate a different home for a period, the exemption can be split — but cleanly only if each of you owns 50% or less of the home you nominated. The moment one spouse owns more than 50% of either property, the exemption on that property is halved for the overlap period. The flag to watch is always: does one spouse own more than half of either home?

Transfers between separating spouses can defer CGT

When an asset moves between spouses because of a relationship breakdown under a court order or binding financial agreement, CGT rollover applies automatically — the transferring spouse disregards the gain or loss, and the receiving spouse takes on the original cost base and acquisition date (which counts toward the 12-month CGT discount). A private or informal split does not get this rollover: the transferring spouse is taxed on any gain. This is a get-advice area.

Splitting super contributions to a spouse

You can apply to split up to 85% of your concessional (before-tax) super contributions to your spouse's fund each year. It doesn't create a deduction, but it evens up balances — useful for keeping each partner under the $3 million Division 296 threshold, getting both balances working under the transfer balance cap, and for couples with an age gap who want to reach preservation age at different times.

5 expensive spouse tax mistakes

Also worth knowing: temporary separations (holidays, work travel) don't end the spouse relationship for these tests — the question is whether you're a couple on a genuine domestic basis. And the return lets you consent to use your refund to repay a spouse's Family Tax Benefit or Child Care debt, which needs their authority to quote their Customer Reference Number.

Common spouse tax planning strategies

Once the reporting is right, the spouse relationship opens up planning levers. These are general strategies, not personal advice — and note that anything touching how assets or contributions are structured is financial advice that belongs with a licensed adviser.

Frequently asked questions

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