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How to Treat a Mixed-Use Property for Tax Purposes

Published 26 June 2026 · Last updated 26 June 2026

Quick Answer

Treating a mixed-use property for tax involves apportioning expenses and income between residential and commercial parts. Under **Division 40** for plant and equipment and **Division 43** for capital works, depreciation can be claimed proportionally. GST implications and CGT may also vary depending on the property's use. Consult a Chartered Quantity Surveyor and accountant for precise calculations.

Handling the tax treatment of a mixed-use property, which combines both residential and commercial elements, requires careful consideration of several factors. The key is to appropriately allocate income and expenses, including depreciation and GST, between the different parts of the property. Under Division 40 of ITAA 1997, you can claim depreciation on plant and equipment, while Division 43 allows for capital works deductions. The challenge lies in accurately apportioning these deductions based on the property's use.

A common misconception is that the same rules apply uniformly across the entire property, but in reality, each portion must be treated according to its specific use. This means that expenses, such as interest on a loan, must be divided in line with the income-generating capability of each section. Additionally, GST may apply to the commercial portion, affecting the overall tax treatment.

To see how this plays out, consider a mixed-use property in Sydney valued at $1.2 million, consisting of a ground-floor retail space and an upstairs apartment. Suppose the retail space generates $60,000 annually, while the apartment earns $30,000 in rent. You would apportion the building's depreciation and any applicable expenses based on the income ratio. If the total depreciation claimable under Division 43 is $10,000, then $6,667 would be attributed to the commercial space and $3,333 to the residential.

In our experience reviewing thousands of properties across Australia, we often find that investors miss opportunities by not claiming full deductions available under each division. Another common issue is the incorrect application of GST, particularly when the commercial portion is leased. Investors also frequently overlook the impact on CGT; the commercial portion may not be eligible for the main residence exemption, potentially leading to a higher tax bill upon sale.

The answer can differ depending on your situation. If your property was acquired post-9 May 2017, the ability to claim Division 40 deductions on second-hand plant and equipment will differ based on whether the property is residential or commercial. For pre-1987 buildings, significant improvements could make them eligible for Division 43 deductions. If an SMSF owns the property, different rules may apply regarding income and expenses.

Given the complexities involved in apportioning expenses and understanding tax implications across different property uses, it's advisable to engage both a Chartered Quantity Surveyor and an accountant. They can ensure that all aspects of your property's tax treatment are optimised and compliant with ATO guidelines.

  • Review your property's income and expense allocations between residential and commercial uses.
  • Consult with a Chartered Quantity Surveyor to maximise your depreciation claims.
  • Confirm GST obligations for the commercial portion with your accountant.
  • Evaluate the potential CGT implications for each part of the property.
  • Keep detailed records of all expenses and income for accurate apportionment.
  • Consider professional advice to ensure compliance and optimised tax outcomes.
  • Frequently Asked Questions

    How do I apportion expenses for a mixed-use property?

    Expenses should be divided based on the income-generating potential of each part of the property. This typically involves calculating a percentage based on rental income from each section.

    Does a mixed-use property affect GST registration?

    Yes, if the commercial portion of your property earns above the GST threshold, you must register for GST and remit it on commercial income.

    Are there state-specific considerations for mixed-use properties?

    While federal tax rules apply uniformly, state-specific considerations such as land tax may vary. Check with your state's revenue office for details.

    How does a mixed-use property affect my tax return?

    You must report income and expenses separately for residential and commercial parts, and potentially file additional schedules for GST if applicable.

    Can I claim the main residence exemption on a mixed-use property?

    The main residence exemption typically only applies to the residential portion. The commercial part is generally subject to CGT.

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    Written by Koste Team · Koste Chartered Quantity Surveyors · AIQS Member · RICS Member · TPB Registered · 1300 669 400 · info@koste.ai