CGT Grandfathering Rules and Why a 1 July 2027 Valuation Is Critical

The Federal Government's tax reforms have fundamentally changed how future capital gains on investment properties will be calculated.

With the enactment of the Treasury Laws Amendment (Tax Reform No. 1) Act 2026, Australia is moving away from the long-standing 50% Capital Gains Tax (CGT) discount for future gains and introducing a new cost-base indexation framework for gains accruing from 1 July 2027. Existing property owners, however, have been granted important transitional protections. [legislation.gov.au], [ato.gov.au]

For many investors, taking the right action before 1 July 2027 could significantly affect the amount of tax paid when a property is eventually sold.

What Has Changed?

Historically, individuals and trusts who held an investment property for more than 12 months were generally entitled to a 50% CGT discount on their capital gain.

Under the new legislation, gains accruing from 1 July 2027 onwards will be subject to a different calculation methodology based on cost-base indexation and minimum tax rate provisions. The Government has, however, provided grandfathering rules to ensure capital growth that occurred before the commencement date continues to receive protection under the previous system. [ato.gov.au], [aph.gov.au]

Understanding the Grandfathering Rules

A useful way to think about the reforms is that they effectively divide your investment property's capital growth into two separate periods.

Stage 1: Capital Growth Before 1 July 2027

All capital growth accumulated between your original purchase date and 30 June 2027 is protected under the transitional grandfathering provisions.

This means the value increase that has already occurred before the new rules commence is effectively quarantined from the new system.

To establish this protected amount, investors should obtain an independent market valuation as at 1 July 2027.

That valuation becomes the critical evidence of what the property was worth immediately before the new rules began applying.

Stage 2: Capital Growth From 1 July 2027 Onwards

Once the transition date arrives, the property's market value at 1 July 2027 effectively becomes the starting point for measuring future gains.

Any capital growth occurring after that date will fall under the new CGT regime rather than the traditional 50% discount framework. [ato.gov.au], [aph.gov.au]

Why Is a Valuation So Important?

Many investors assume they can simply obtain a retrospective valuation years later when they eventually sell their property.

While that may be possible in some cases, obtaining a valuation contemporaneously provides far stronger evidentiary support should the Australian Taxation Office ever review the calculation.

A professionally prepared valuation establishes:

• The property's market value at the transition date
• The amount of growth protected under the grandfathering provisions
• A clear baseline for future CGT calculations
• Supporting documentation that can be retained with your tax records

For investors planning to hold property for many years, this document could become one of the most valuable tax records they possess.

Who Should Obtain a Valuation?

You should strongly consider obtaining a valuation if you own:

• Residential investment properties
• Commercial investment properties
• Properties held personally
• Properties held in trusts
• Properties held jointly with family members or business partners

Even if there are no immediate plans to sell, recording the property's value at the transition date may help preserve future CGT outcomes.

Who Can Complete the Valuation?

The valuation should be undertaken by an appropriately qualified independent property valuer.

A valuation prepared by a recognised professional provides the strongest support for future tax purposes and should be retained indefinitely with your property records.

Recommended Action

While 1 July 2027 may seem a long way off, valuers are expecting substantial demand as the transition date approaches.

Duo Tax has established a dedicated service for transition-date CGT valuations and is encouraging investors to register their interest early.

Book your valuation here:

DuoTax CGT Property Valuation 1st July 2027

Once your valuation is completed, we recommend providing a copy to our office so it can be retained with your CGT records and referenced when calculating future capital gains.

Final Thoughts

The introduction of the new CGT regime represents one of the most significant changes to investment property taxation in recent years. While the grandfathering provisions are designed to protect existing owners, those protections work best when supported by proper documentation.

For most property investors, arranging a professional valuation as at 1 July 2027 will be a simple and relatively inexpensive step that could provide substantial tax benefits and certainty in the future.

If you would like to discuss how these changes may affect your investment properties, trust structures, succession planning, or broader tax strategy, please contact our office.

Frequently Asked Questions

Do I need a valuation if I don't plan to sell anytime soon?

Yes. Even if you hold the property for another 10 or 20 years, having an ATO-compliant market valuation as at 1 July 2027 proves your Stage 1 value when you eventually sell. Retrospective valuations completed years later are far more costly, complex, and prone to ATO challenges.

Can I use a real estate agent's appraisal?

No. The ATO strictly requires CGT market valuations to be completed by a qualified independent property valuer or quantity surveyor to meet official tax reporting standards.

What should I do after receiving my valuation report?

Once Duo Tax completes your valuation report, forward a copy to our accounting team. We will record your grandfathered Stage 1 cost base on file to ensure seamless tax reporting upon sale.

If I am an Australian resident holding UK property do I still need a 1 July 2027 CGT valuation?

Yes - obtaining a market valuation as of 1 July 2027 is strongly recommended (and practically required) if you plan to hold the UK property beyond 1 July 2027.

What about foreign residents holding Australian property, do they still need the 1 July 2027 valuation?

For foreign tax residents holding Taxable Australian Property (TAP)—such as residential or commercial real estate in Australia—the situation is different from Australian residents.

Generally, NO - a 1 July 2027 valuation is usually unnecessary for foreign residents, unless you plan to move back and become an Australian resident again in the future.

Summary Checklist: 1 July 2027 CGT Valuation Requirements

Disclaimer: This article provides general information only and does not constitute personal taxation advice. Tax outcomes depend on individual circumstances, and professional advice should be obtained before acting on any information contained in this article.