Property valuation for capital gains tax: when you need one

A property valuation for capital gains tax is an independent assessment of a property's market value at a set date, used to work out your capital gain or loss when a CGT event happens. You need one whenever the Australian Taxation Office relies on market value instead of a sale price: a change of use, an inherited property, or a transfer to related parties. This guide explains when a capital gains tax (CGT) valuation is required, why a retrospective valuation is often involved, and who should prepare it. It is general information, so confirm your position with a qualified adviser.

Key takeaways

• A capital gains tax valuation sets or supports the market value used to calculate a capital gain or loss.
• You usually need one for a change of use, an inherited property, or a transfer that is not at arm's length.
• Many CGT property valuations are retrospective, assessing value at a past date such as the date a home was first rented.
• The valuation feeds the cost base, which drives the taxable capital gain and the tax payable.
• A defensible valuation from a qualified valuer protects you if the ATO questions the figure.

What is a property valuation for capital gains tax?

Capital gains tax applies when you dispose of a property asset, such as an investment property, for more than it cost you. The gain is the difference between what you receive and the property's cost base, and a capital loss arises if it is worth less.

A property valuation for capital gains tax provides the fair market value the calculation needs when there is no ordinary sale price to use. It is an evidence-based valuation report, not a real estate agent's appraisal, prepared so it holds up for tax purposes.

When do you need a CGT property valuation?

Certain events trigger the need for a valuation for capital gains rather than a guess.

Renting out your former main residence

If your home stops being your main residence and becomes a rental property, a special rule can apply. Under the home first used to produce income rule, if you would have qualified for a full main residence exemption beforehand, you are taken to have acquired the dwelling at its market value when it was first used to produce income. That makes a valuation at the date the property was first rented essential.

Inherited property

When you inherit property, the cost base depends on the deceased's situation. If they acquired the property before 20 September 1985, or it was their primary residence and not producing income when they died, your cost base is generally its market value at the date of death. A date-of-death valuation, which is retrospective, fixes that figure so your future CGT is worked out correctly.

Transfers to related parties

If you transfer property to family members for less than it is worth, the market value substitution rule applies. The ATO treats the disposal as happening at market value, whatever actually changed hands, so gifting property or selling it cheaply to relatives still creates a CGT event a valuation should record.

Retrospective CGT valuations

Many capital gains tax valuations look backwards. A retrospective valuation assesses what a property was worth at a past date, using comparable sales from that period.

Common dates include the day a home was first rented, the date of death for an inherited property, or the point a property changed use. It is far easier to value close to the event, but a retrospective report can still be prepared years later when needed.

How the valuation fits the CGT calculation

The valuation sets one end of the sum. Your capital gain is broadly the proceeds at the CGT event, less the cost base.

Because the report can set the cost base or the disposal value, an accurate figure directly affects your taxable capital gain, your tax liability and the tax you eventually pay when selling. A weak figure can mean more tax, or a challenge from the tax office.

Why the value at a date matters more than ever

CGT rules are changing. From 1 July 2027, the 50% CGT discount is being replaced with cost base indexation and a 30% minimum tax rate, with new rules applying to capital gains accrued after that date.

That makes a defensible market value around a transition date valuable, because it helps separate the gain taxed under the old rules from the gain taxed under the new ones. Our 2026 Budget CGT and negative gearing guide covers the changes in detail.

Who should prepare a CGT property valuation?

For a figure the ATO will accept, use a qualified, independent professional valuer. A certified property valuer or certified practising valuer who is a member of the Australian Property Institute carries real weight.

They prepare a report documenting the market value, the date, and the comparable evidence behind it. That is what makes a capital gains tax valuation defensible, rather than just a number, and it gives you evidence if your position is ever reviewed. Because the amounts are often large, and unsupported figures risk adjustments and ATO penalties, the cost of a proper valuation is small next to the tax at stake.

How Valato helps

Valato provides independent property valuations for capital gains tax across Australia, both current and retrospective, dated to the exact point in time your CGT event requires.

Each report pairs a defensible market value with comparable sales evidence, ready to support your cost base at tax time. Compare the valuation options or order a valuation to lock in a supportable figure, and always confirm the tax treatment with your accountant.

The bottom line

A property valuation for capital gains tax turns market value into a defensible number for your CGT calculation. You need one for a change of use, an inherited property, or a transfer that is not at arm's length, and it is often a retrospective valuation to a past date. Get a proper, evidence-based report from a qualified valuer, confirm the treatment with your adviser, and your capital gains tax position rests on solid ground.

Frequently asked questions

General information only: This article is general in nature and does not take into account your individual circumstances. It should not be relied on as tax, financial or legal advice. Capital gains tax rules are complex and changing; confirm the current rules and your own position with a qualified professional before making decisions about your property or tax position.