A property sale can look straightforward until the contract is ready to sign. A Sydney doctor may have rented out a spare room, a new migrant may have changed tax residency, and a family trust may be deciding whether to sell before 30 June. Each detail can affect the taxation on property sale, and settlement date is often not the date that determines when the capital gain is reported.
This guide explains the Australian rules that matter most before signing a contract, including capital gains tax (CGT), the main residence exemption, the six-year rule, mixed-use property, foreign resident withholding and contract timing. It also identifies where professional judgement, records and pre-settlement review can produce a more reliable outcome than a generic calculator. A preliminary estimate from the RealtyAPI.io property tax tool may help frame questions, but it shouldn't replace a review of ownership history, residency and supporting records.
Who this article is for: medical professionals, business owners, property developers, family trusts, SMSF trustees, and new migrants dealing with an Australian property sale.
Currency note: This article reflects Australian rules, thresholds and regulator guidance current as at 08/2026. Time-sensitive figures are current as at 08/2026.
When You Sell Property in Australia
A property owner preparing for auction often starts with the sale price, agent's commission and settlement date. Tax usually enters the conversation later, sometimes after the contract has already been signed. That sequence can create avoidable pressure, particularly where the property was once a home, later rented, partly used for business, or held through an entity.
Australian taxation on property sale involves several overlapping rules. CGT may apply to the gain, but the main residence exemption can remove some or all of that gain where its conditions are met. Foreign resident capital gains withholding can also affect settlement cash flow, while the contract date generally determines the income year in which the CGT event is reported.
Practical rule: Treat the proposed contract date as a tax decision point, not just an administrative milestone.
The history of the property matters as much as its current use. A professional who converted a home into an investment property, a developer who acquired land for profit-making activity, and a migrant who became an Australian tax resident may each face different outcomes even if the properties have similar sale prices. The same applies to a family trust, where the trust generally calculates the gain before distributing the taxable amount to beneficiaries.
The related stamp duty guidance can also be relevant when a transaction involves transfers, restructuring or a change in ownership rather than a simple third-party sale. Stamp duty and CGT are different taxes, so one analysis doesn't answer the other.
The practical objective is to establish the likely tax treatment before signing, preserve evidence for the cost base and mixed-use calculation, and identify whether withholding documentation is needed. That approach works better than relying on settlement timing or treating the main residence exemption as automatic.
How Capital Gains Tax Works on Property
Capital gains tax is part of the income tax system, rather than a separate tax return. A capital gain generally begins with the sale proceeds and is reduced by the property's cost base. The cost base can include the acquisition amount, eligible acquisition costs, documented capital improvements and relevant selling expenses. The exact components depend on the records and the nature of the expenditure.
CGT came into effect on 20 September 1985. The Australian Taxation Office (ATO) says property acquired before that date is generally exempt from CGT on sale, although later improvements or additions may create a taxable component. A single property sale can therefore contain both an exempt pre-CGT asset component and a taxable post-CGT improvement component. See Everglow's explanation of capital gains tax on Australian property for related structuring issues.
The calculation starts with ownership history
The basic sequence is:
- Establish the asset history: Confirm the acquisition date, ownership entity, use of the property and any changes in ownership.
- Build the cost base: Collect contracts, settlement statements, improvement invoices and sale expenses. An expense that has already been claimed as a deduction may require separate treatment.
- Identify the CGT event: The CGT event generally occurs when the sale contract is signed, not when settlement occurs. The ATO says the gain or loss belongs in the tax return for the income year in which the contract is signed.
- Apply available concessions: Where the main residence exemption doesn't apply, an eligible Australian resident may generally reduce a capital gain by 50% if the property was owned for at least 12 months, subject to the relevant conditions and exclusions. The ATO's CGT discount guidance sets out the rule.
The discount doesn't turn a capital gain into tax-free cash. The discounted gain generally enters the taxpayer's assessable income and may be taxed at the applicable marginal rate. A trust, company or foreign resident can require a different analysis, so the ownership entity should be identified before anyone models the result.
Main Residence Exemption and the 6-Year Rule
A dwelling may qualify for the main residence exemption when it has been the home of the owner, the owner's partner and dependants for the whole ownership period, hasn't been used to produce income, and is on land of 2 hectares or less, as explained by the ATO in its main residence eligibility guidance. If those conditions are satisfied, the capital gain is generally ignored and a capital loss is disregarded.
The exemption isn't merely a label attached to a property. Actual occupation, income-producing use, land size and ownership history all matter. Where land exceeds 2 hectares, only up to 2 hectares can generally fall within the exemption, with the remaining land requiring separate consideration.
Temporary absence can change the result
The ATO's six-year rule allows a former home to retain main residence treatment for up to 6 years while it produces rental income, subject to the relevant conditions. If the former home isn't used to produce income, the ATO says it can continue to be treated as the main residence indefinitely. The rule can be useful for someone who moves for work and rents out the former home, but it isn't a blanket exemption for every period or every property.
A seller should also examine whether another dwelling was treated as the main residence during the same period. Overlapping claims, changes in occupancy and repeated periods of rental use can affect the calculation.
Foreign residency creates a separate restriction. For property sold after 30 June 2020, a foreign resident generally can't claim the main residence exemption unless a narrow life-events test applies. Residency should therefore be assessed for the relevant tax periods, rather than assumed from citizenship, visa status or the seller's current address. A high-level discussion of the rule can be supplemented with expert advice on main residence, while a transaction-specific review is available through Everglow's main residence exemption and six-year rule resource.
Mixed-Use Properties and Partial Income Production
The main residence exemption becomes more technical when a home has both private and income-producing use. Renting a room, operating a business from part of the dwelling or converting the home into an investment property can create a taxable proportion. The ATO says the assessable capital gain is generally apportioned by floor area and the days used to produce income.
The calculation may also use a market-value starting point where a home was first used to produce assessable income. That valuation can become critical evidence, particularly when the property was occupied privately for years before the first rental or business use. A casual estimate made after the sale may be difficult to defend.
Records matter more than labels
A practical file may include:
- Use evidence: tenancy agreements, room-rental records, business-use dates and periods of private occupation.
- Area evidence: floor plans or measurements showing the income-producing portion.
- Valuation evidence: a suitably supported market valuation at the date the home first produced assessable income.
- Cost records: improvement invoices and sale costs, with deductions considered separately.
The table below illustrates the structure of an apportionment calculation. It doesn't provide a tax outcome because the taxable gain percentage depends on the actual facts and the applicable valuation.
| Scenario | Floor Area Used for Income | Days Used for Income | Taxable Gain Percentage |
|---|---|---|---|
| Private home with one rented room | Part of the dwelling | Temporary rental period | Calculated using both factors |
| Home converted to full rental use | Entire dwelling | Rental period before sale | Calculated by the relevant ownership period |
| Home office with income-producing use | Dedicated business area | Business-use period | Calculated using area and days |
The all-or-nothing assumption doesn't work for mixed-use property. A seller may have a substantial exempt component and a smaller taxable component, but the evidence must support the split. Interest and home-business issues can also require separate treatment, so review home interest deduction considerations before relying on a tax outcome inferred from the CGT calculation alone.
Foreign Resident Withholding and Residency Tests
Foreign resident capital gains withholding is a settlement cash-flow rule, not a final calculation of the seller's capital gain. From 1 January 2025, the purchaser must generally withhold 15% of the value of Australian property unless the vendor provides a valid clearance certificate, or a variation notice where the relevant foreign-resident process applies. The ATO explains the clearance process for Australian residents in its Australian resident clearance certificate guidance.
The amount is applied to the sale price, or to market value where a transaction isn't conducted at arm's length. That means withholding can occur even where the seller ultimately has no capital gain, or where the final tax payable is lower than the amount withheld. The seller generally claims the withheld amount as a credit through the relevant tax return process.
Documentation should be settled before settlement
The former regime applied a 12.5% withholding rate from 1 July 2017 to 31 December 2024 for property valued at $750,000 or more, according to the ATO's foreign resident withholding overview. The current rule is broader, so vendors and conveyancers need to address residency documentation early rather than waiting for settlement.
Residency is a tax question, not merely a citizenship question. A new migrant, an Australian resident working overseas, or a seller who left Australia may need to review residency for the relevant period and the availability of the main residence exemption separately.
Settlement control: Confirm the clearance certificate or variation position before the contract and settlement timetable become difficult to change.
Everglow's foreign resident capital gains withholding guidance can help identify the documentation issues that should be raised with the conveyancer and tax adviser.
Timing Rules and Tax Planning Strategies
A delayed settlement doesn't generally delay the CGT event. The contract date determines the income year in which the gain or loss is reported, and the ATO calculates total days owned using the purchase and sale contract dates rather than settlement dates. This is particularly important for a contract signed near 30 June, where the gain may fall into a different income year from the one the seller expected.
The timing analysis should be completed before signing, especially where the seller is refinancing, negotiating a delayed settlement, transferring property through an estate or considering a related-party transaction. The legal form, market value, ownership history and purpose of the transaction can all affect the tax treatment.
What should be checked before the contract is signed
Start with the records, not the forecast sale price. Confirm the original purchase contract, acquisition costs, capital improvements and selling expenses. Improvements should be supported by invoices and payment evidence, while any amount already claimed as a deduction may not be added to the cost base again.
Holding period can matter where the CGT discount is potentially available. A seller who is close to the 12-month ownership requirement should obtain advice before bringing the contract date forward, but commercial considerations may outweigh a tax benefit. A discount also doesn't apply automatically to every owner or every gain.
Other decisions require specialist review:
- Related-party transfers: Market value and the actual CGT event may need careful assessment.
- Estate transactions: The deceased estate, beneficiary and eventual sale can have different tax questions.
- Refinancing: A refinance doesn't itself determine CGT, but transaction documents can reveal a change in ownership or use.
- Developments: Profit-making activity may be taxed as ordinary income rather than treated solely as a capital gain.
- Small-business concessions: A developer or business owner may need to test the specific eligibility rules rather than assume a concession applies.
Worked Example: The Nguyen Family Property Trust
The Nguyen family in Parramatta holds an investment property through a family trust. For illustration, assume the trust acquired the property in 2015 for $650,000, incurred $80,000 of documented capital improvements in 2018, and signs the sale contract in March 2026 for $1,050,000. The family is deciding whether signing before 30 June fits its cash-flow and distribution plans.
On the stated figures, the preliminary cost base is $730,000, comprising the $650,000 acquisition amount and $80,000 of capital improvements. Before considering selling costs, adjustments, losses or other exclusions, the indicative capital gain is $320,000, calculated as $1,050,000 less $730,000.
The property has been held for more than 12 months, so the trust may be able to apply the 50% CGT discount to an eligible gain. On the simplified figures, that produces a discounted gain of $160,000 before considering any capital losses, deductions, exemptions or other adjustments. This is not necessarily the family's final tax bill. The trust generally calculates the gain and may distribute the resulting taxable amount to beneficiaries, with the tax outcome depending on the trust deed, resolutions, beneficiary circumstances and applicable tax rules.
The date decision
Because the contract is signed in March 2026, the CGT event generally belongs to the income year containing that contract date, even if settlement occurs later. Signing before 30 June may therefore bring the gain into that income year, while delaying the contract could move the event into the following income year. That decision should be weighed against the commercial terms, financing, market conditions and the family's distribution position.
The example changes if the property was mixed-use, if improvements were partly deductible, if the trust has capital losses, or if the transaction is part of a profit-making development activity. A foreign resident beneficiary or withholding issue could also affect cash flow without changing the underlying CGT calculation in the same way.
The core answer is that taxation on property sale depends on the property's use, ownership entity, residency, records and contract date. The right approach depends on your circumstances, so review those matters before signing rather than relying on settlement timing or a headline exemption.
If you would like clarity on how these principles may apply to your own circumstances, contact Everglow on 1300 913 929 or email contact@everglow.au.
To book directly: Book a meeting with Panbo.
Tags: Australian property tax, taxation on property sale, capital gains tax, main residence exemption, six-year rule, foreign resident withholding, property investment, Australian tax planning
Want help applying this to your situation?
Every situation is different. Book a time with our team to talk it through, or call us on 1300 913 929.
Book a free meetingAustralian tax guide →Estimate your fees →
Keep exploring