CGT Valuation When You Move Out of Your Home: Do You Need One?

Plenty of Australians move into a new place and keep the old one as a rental. It feels like a practical decision, and the tax side often gets left until tax time. The trouble is that a capital gains tax (CGT) question that seemed simple at the time can become much harder to answer years later. What was your home worth on the day you first rented it out? Depending on your situation, a historical market assessment can help establish that earlier value and support your CGT calculation.

This article covers when a CGT valuation is needed for a property you’ve moved out of, how the six-year rule fits in, and what evidence to keep. It’s general information rather than tax advice, so your accountant should confirm how the rules apply to you.

Summary

When you move out of your home and rent it out, the main residence exemption doesn’t always continue on its own. In many cases the six-year absence rule lets you keep the exemption for up to six years, provided you meet the conditions. Once that period ends, or if the rules point to a different starting value, the market value of the property on a specific past date can become the figure your tax position depends on. That’s where a retrospective valuation comes in. It’s an estimate built from historical sales and rental evidence, so the quality of your records matters as much as the valuer’s report. Before you sell, work out the key dates, keep rental records, and talk to your accountant about which rule applies. Starting early makes the eventual valuation much easier and cheaper to prepare.

What Is a CGT Valuation for a Former Home?

A CGT valuation is a retrospective valuation: an independent estimate of what a property was worth on a specific date in the past. That date is usually when the property stopped being your main home and started producing rental income, or the date a particular CGT rule applies.

You’ll also hear it called a historical valuation. The idea is the same. The valuer looks back at the market as it stood on that date and works out the value using comparable sales, rental evidence and what the property looked like at the time.

Why the main residence exemption isn’t always the end of the story

Your main home is generally exempt from CGT when you sell it. That’s the main residence exemption, and most people never think about it while they live in the property.

Things change when you move out and rent it. The exemption can continue for a while, but only if you meet certain conditions. If you don’t, or once those conditions run out, part of your gain may be taxable, and the value on a particular past date starts to matter.

How the Six-Year Rule Keeps the Exemption Alive

The six-year absence rule may allow you to continue treating your former home as your main residence for up to six years while it is used to produce income, subject to eligibility requirements.

If you move out, rent the property and sell within the applicable six-year period, the entire gain may remain exempt.

Those conditions generally include:

• The home was your main residence before you moved out.
• You don’t treat another property as your main residence for the same period, with limited overlap allowed when you move into a new home.
• You choose to apply the six-year rule, and you should be able to show that you did.

Here’s a hypothetical example. Tom and Mei bought a townhouse in Penrith in 2016 and lived in it until 2021. They then bought a bigger home in Blacktown and rented out the townhouse. If they sell the townhouse in 2026, they’re five years past the move-out date, so the six-year rule may cover the whole sale. The valuation becomes important if they wait longer than six years, or if the rule doesn’t apply for some other reason.

When Does a CGT Valuation Become Necessary?

A CGT valuation isn’t needed in every case. These are the situations where it usually matters.

You rent the property beyond six years

Once the six-year period runs out, the exemption no longer covers the rental period in the same way. For a dwelling that was first used to produce income, the market value on that first income date is generally used as the cost base for the taxable part of the gain. A valuation is the best way to evidence that figure.

You rented it from the day you moved out and didn’t use the six-year rule

If you never chose the six-year rule, the market value on the day rent began is usually the starting point for the taxable portion. That means the valuation should target that date, not a date years later. Getting the timing right is the difference between a clean calculation and an expensive reconstruction.

You want the figure on record early

Some owners get a retrospective valuation done when they move out, so the figure is recorded while the evidence is fresh. This isn’t a legal requirement in every case, but it can save time and stress later.

The ATO asks questions

If the Australian Taxation Office queries your gain, a retrospective valuation supported by clear evidence can help explain how you reached your figure.

What a Retrospective Valuation Actually Measures

The valuation estimates market value at a specific date. That’s the price a willing buyer would pay a willing seller in an arm’s length sale, with both parties acting knowingly and without pressure.

To reach that figure, a valuer typically looks at:

• Sales of similar properties close to the relevant date, adjusted for differences
• Rental evidence from the same period, where relevant
• The property’s condition, layout and improvements as they were then
• The zoning and planning controls in place at the time

Records from years ago can be patchy, and in smaller suburbs there may be few sales to compare. A good valuer will say so in the report. A retrospective valuation is an estimate, not a precise figure, and the strength of the report depends heavily on the evidence behind it.

What to gather before you book a valuer

• Your purchase contract and settlement statement
• Dates you moved out and when rent started
• Lease agreements and rent records
• Photos, floor plans and renovation receipts from the time
• Council approvals for any major works

Common Misconceptions About Moving Out and CGT

“Renting it out automatically means I pay CGT.” Not necessarily. The six-year rule may keep the exemption in place.

“Any valuation will do.” A current appraisal, or a valuation at the wrong date, won’t answer the question. The date is what matters.

“An agent’s estimate is good enough.” As our guide to using an agent’s appraisal for CGT explains, a selling-price estimate may not provide the historical evidence needed for a tax calculation.

“I only need to worry about this when I sell.” You may need evidence years before a sale, so keeping records early helps.

Practical Steps Before a CGT Valuation

1. Note the date you moved out and the date rent started.
2. Keep records of rental income and deductible expenses from the start.
3. Ask your accountant whether the six-year rule applies, and track the six-year date.
4. If the cost base depends on a past value, get a retrospective valuation at the relevant date.
5. Check the valuer’s registration with the relevant state body, as valuer registration is handled at state level in Australia.

Frequently Asked Questions

Do I need a CGT valuation if I move out and rent my home?

Not always. If you meet the six-year rule conditions and sell within six years, the exemption may cover the whole gain. A valuation becomes important when the cost base depends on a past value, such as after the six-year period ends or where the six-year rule wasn’t used.

How long can I rent out my home and keep the main residence exemption?

Generally up to six years under the absence rule, as long as the conditions are met. The period is usually counted from the date you move out.

What date does a CGT valuation need to be for?

Usually the date the property first started producing rental income, or the date a particular CGT rule applies. Your accountant can confirm the right date for your situation.

Can I use a real estate agent’s appraisal instead?

Agent appraisals are usually prepared to support a sale, and they often don’t meet the standard needed for tax purposes. A formal retrospective valuation with supporting evidence is generally the more reliable option.

Does the valuation have to come from a registered valuer?

Valuers are registered at state level in Australia. A registered valuer’s formal report gives you a professionally prepared, documented figure. Check with your accountant about what evidence they’ll need.

Conclusion

Moving out of your home doesn’t automatically trigger CGT, but it does change how the exemption works. The six-year rule gives many owners breathing room. Once that time runs out, or where the rules point to the date you began renting, the market value on that past date becomes important. Keep clear dates and records from the start, and speak to your accountant before deciding how to proceed.

Talk to Registered Property Valuers

If you’re working out whether you need a CGT valuation for a home you’ve moved out of, Registered Property Valuers can prepare a retrospective valuation with supporting evidence for the date your tax position depends on. Call Registered Property Valuers on +61 438 080 786 to talk through your situation. Your accountant or tax adviser is still the right person to confirm how the tax rules apply to you.