Updated 10 October 2026
A real estate agent's appraisal is a marketing estimate, not evidence of market value. The ATO's guidance says valuations by professional valuers are more credible than those prepared by anyone else, and an unsupported figure exposes you to shortfall penalties of 25 to 75 per cent. A signed Certified Property Valuer report is the defensible standard.
At a glance
- A real estate agent appraisal is a marketing estimate, not evidence of market value for CGT
- The ATO expects tax valuations to be objective, supportable and properly reasoned
- Relying on a professional valuer supports the safe harbour against shortfall penalties under section 284-90
- Shortfall penalties run 25 to 75 per cent of the tax shortfall where a figure cannot be supported
- A desktop valuation from a Certified Property Valuer is $297 inc. GST for residential, delivered in 24 to 48 hours
In this guide
Appraisal vs valuation: the actual difference
An agent appraisal answers a marketing question: what listing price might attract a buyer? It is free because it is a pitch for the listing. It carries no methodology, no comparable sales analysis you can hand to a reviewer, no independence, and no professional accountability if it is wrong. Agents are also structurally motivated to flatter the number.
A CGT valuation answers a legal question: what was the market value of this property at a specific date, determined on the willing buyer, willing seller basis the courts have applied since Spencer v Commonwealth (1907)? It is prepared by a qualified valuer, states its methodology, analyses actual comparable sales from around the valuation date, and is signed by someone whose professional standing depends on it being right.
A bank valuation is not a substitute either. It is prepared for the lender's risk position, is typically conservative, is addressed to the bank, and does not target the market value definition the tax law requires.
What the ATO says
The ATO's Market valuation for tax purposes guidance is direct on the hierarchy of evidence. Valuations undertaken by professional valuers are more credible than those provided by someone who is not a professional valuer. The guidance also sets out what a valuation report should contain: the purpose and scope, the asset details, the valuation date, whether it is retrospective, the methodology, and the evidence supporting the value.
An agent's one-page appraisal contains almost none of that. When the ATO reviews a CGT calculation, the question is whether the market value figure can be objectively supported. A letter that says "we would market this property at $850,000 to $900,000" is an opinion about a listing strategy, and reviewers treat it that way.
The penalty risk of a weak number
Get the value wrong in your favour and the exposure is not just the extra tax. Under section 284-90 of Schedule 1 to the Taxation Administration Act 1953, administrative penalties apply to a tax shortfall:
- 25 per cent of the shortfall for failing to take reasonable care.
- 50 per cent for recklessness.
- 75 per cent for intentional disregard of the law.
Interest charges apply on top, and from 1 July 2025 general interest charge and shortfall interest charge are no longer deductible, so the true cost of an amended assessment has gone up. Relying on a mate's appraisal for a six-figure cost base is exactly the kind of thing the reasonable care standard is measured against.
Penalty risk
Where this bites hardestRelated-party transfers, deceased estates, home-to-rental conversions and the coming 1 July 2027 cost base reset all rest on a market value with no contract price behind it. These are precisely the transactions the ATO's data matching surfaces, and precisely where an appraisal-based figure falls over.
The safe harbour a professional valuation gives you
The ATO's guidance offers a meaningful protection: generally, if you engage and properly instruct a professional valuer, you will not be liable for penalties even if the ATO later finds the valuation deficient. The tax position can still be adjusted, but the penalty exposure largely disappears, because obtaining a professional valuation is itself the exercise of reasonable care.
No appraisal, bank letter or online estimate carries that protection. For a residential report at $297, the valuation is the cheapest risk transfer in the entire transaction, and the fee itself is not lost money: a valuer's fee for a CGT valuation is an incidental cost that can form part of your cost base under section 110-35, or in some cases is deductible as a cost of managing your tax affairs. Your accountant applies one treatment, not both.
The stakes rise from 1 July 2027, when the CGT changes make the market value at the reset date a permanent part of your cost base. Our CGT calculator shows what a difference in that figure does to the tax.
Need a number the ATO will respect?
Independent CGT valuations signed by a Chartered Accountant and Certified Property Valuer. $297 residential, $595 commercial, incl GST, delivered in 24 to 48 hours, Australia-wide.
Start your orderHow it worksSide by side
| Agent appraisal | Bank valuation | Certified Property Valuer report | |
|---|---|---|---|
| Purpose | Win the listing | Lender's security risk | Market value at a defined date |
| Independence | No | Addressed to the bank | Yes, signed and accountable |
| Methodology and comparable sales | Rarely documented | Not disclosed to you | Fully documented |
| Retrospective dates | No | No | Yes, any past date |
| ATO credibility | Low | Low | The standard the guidance describes |
| Penalty safe harbour | No | No | Yes, when properly instructed |
| Cost | Free | Paid by or via the bank | $297 residential, $595 commercial |
Common questions
Will the ATO accept a real estate agent's appraisal?
The ATO treats an agent appraisal as low-credibility evidence. Its guidance states that valuations by professional valuers are more credible than those prepared by anyone else, and an appraisal lacks the methodology, independence and comparable sales analysis a review looks for. Relying on one risks adjustment and shortfall penalties.
What valuation does the ATO require for CGT?
An objective, evidence-based market valuation at the relevant date, documenting purpose, methodology and comparable sales, prepared consistently with the ATO's Market valuation for tax purposes guidance. A report signed by a Certified Property Valuer meets that standard and attracts the penalty safe harbour for properly instructed professional valuations.
Can I use a bank valuation for CGT?
It is a poor fit. Bank valuations are prepared conservatively for the lender's risk, are addressed to the bank rather than you, and do not target the tax law's market value definition. They carry little more weight than an appraisal in an ATO review.
Is the cost of a CGT valuation tax deductible?
The fee is not wasted either way. It can form part of your cost base as an incidental cost under section 110-35, or in some circumstances be deductible as a cost of managing your tax affairs. Your accountant will apply the correct single treatment.
