---
title: "The Six-Year Tax Clock Hidden Inside Your Home. Most Owners Have No Idea It Exists."
description: "Australia's six-year rule lets you rent out your former home for up to six years without paying capital gains tax. Here is how the clock works, how to reset it, and the traps to avoid."
author: Joey Don
date: 2023-07-03
category: Renovation & Development
url: https://premiumrea.com.au/blog/six-year-rule-capital-gains-tax-exemption-investment-property
tags: ["capital gains tax", "six year rule", "main residence exemption", "tax planning", "investment property", "ATO", "property strategy"]
---

# The Six-Year Tax Clock Hidden Inside Your Home. Most Owners Have No Idea It Exists.

*By Joey Don, Co-Founder & CEO at PremiumRea — 2023-07-03*

> There is a rule in Australian tax law that can save property owners hundreds of thousands of dollars. The six-year CGT exemption lets you rent out your former home while keeping your main residence exemption. Most owners and many accountants do not use it properly.

Last month, a bloke named David called me. IT manager, mid-thirties, the kind of person who reads every clause in a contract before signing. He was holding a letter from the ATO and had already resigned himself to paying $127,000 in capital gains tax on his former home.

I explained one rule to him. Five seconds of silence on the phone. Then: 'You mean the clock just starts again?'

That rule is Section 118-145 of the Income Tax Assessment Act 1997, commonly called the six-year rule. And it might be the most valuable piece of tax legislation that ordinary Australian homeowners consistently fail to use.

## What the Six-Year Rule Actually Says

The rule is straightforward in principle. If you move out of your main residence and start renting it out, you can continue to treat it as your main residence for capital gains tax purposes for up to six years. During that period, if you sell the property, the capital gain is fully exempt from CGT, just as if you had been living in it the entire time.

The conditions are simple. The property must have genuinely been your main residence before you moved out. You can only claim one property as your main residence at any given time. And the absence must not exceed six years if you want the full exemption.

Consider a practical example. You buy a unit in 2015 for $600,000 and live in it for three years. In 2018, you relocate for work and rent the unit out. By 2020, the unit is worth $900,000 and you decide to sell.

The capital gain is $300,000. Under normal rules, you would owe CGT on that amount, potentially $50,000 to $100,000 depending on your marginal tax rate and the 50 per cent discount.

But because you sold within six years of moving out, and the property was genuinely your main residence before that, the entire $300,000 gain is exempt. Zero tax. Not reduced tax. Zero.

Let me add a worked example with actual numbers because the savings become visceral when you see them in dollar terms.

Sarah bought a two-bedroom unit in Brunswick in 2012 for $450,000. She lived in it for four years. In 2016, she moved in with her partner in Northcote and rented out the Brunswick unit.

By 2020, the unit was worth $700,000. Sarah considered selling. The capital gain: $250,000.

Without the six-year rule, the CGT calculation would be: $250,000 gain, minus the 50% discount for holding longer than 12 months = $125,000 assessable. At a marginal tax rate of 37%, the CGT liability would be approximately $46,250.

With the six-year rule, because Sarah sold within six years of moving out (2016 to 2020 = 4 years), the entire gain is exempt. CGT liability: zero.

That $46,250 saving is real money. It is a deposit on the next investment property. It is two years of school fees. It is the difference between financial comfort and financial stress.

Now consider what happens if Sarah does not sell in 2020 but instead moves back into the Brunswick unit for six months in 2021, re-establishing it as her main residence. She then moves back to Northcote and rents the unit out again. The six-year clock resets in 2021. She now has until 2027 to sell the unit tax-free.

By 2027, the unit might be worth $950,000. The gain from the original 2012 purchase: $500,000. If she sells within the six-year window, the CGT exemption covers the entire gain. Zero tax on $500,000 of growth.

The cumulative tax saving from proper use of the six-year rule in this scenario exceeds $90,000. That exceeds the original deposit Sarah paid to buy the property.

## The Clock Resets. That Is the Part Most People Miss.

Here is where the rule becomes genuinely powerful, and where I have seen the most value created for clients.

If you rent out your former home for five years and are approaching the six-year limit, you can move back in and re-establish it as your main residence. You do not need to live there for years. The ATO looks for genuine intention: are you actually residing in the property as your home?

Once you re-establish it as your main residence, the six-year clock resets when you move out again. In theory, you can cycle through this pattern indefinitely: live in the property, move out and rent it for up to six years, move back in, move out again.

The practical effect is that a property can be rented out for decades while maintaining its main residence CGT exemption, provided you periodically re-establish genuine residence.

I want to stress the word 'genuine.' The ATO is not stupid. They will examine your water and electricity bills, your postal address, your electoral roll registration, your bank statement addresses, and whether your personal belongings are in the property. You cannot simply change your driver's licence address and claim the exemption. But if your intention is genuine and your occupation is real, even if temporary, the clock resets.

## Common Scenarios Where the Six-Year Rule Saves Fortunes

Scenario one: the growing family. You bought a two-bedroom apartment as a single person. You get married, have children, and need a bigger home. Instead of selling the apartment and paying CGT, you rent it out and buy a larger house as your new main residence. The apartment can be rented for up to six years while remaining CGT-exempt.

Scenario two: the expatriate. You accept a job in Singapore for three years. Your Melbourne home sits there appreciating. You rent it out while overseas. When you return or sell within six years, the growth is exempt.

Scenario three: the sea change. You move to the coast but keep your Melbourne property as a rental. The six-year clock gives you time to decide whether the move is permanent without being forced into a tax-driven sale.

In each scenario, the alternative, selling the property to avoid future CGT liability, triggers immediate tax and transaction costs. The six-year rule gives you flexibility to defer that decision while the property continues to grow tax-free.

For context, across our 350-plus transactions, a significant number of clients are converting former homes into investment properties. The six-year rule is one of the first things we discuss, because the tax savings can dwarf our entire service fee.

I want to address a nuance that catches many property owners by surprise: the interaction between the six-year rule and rental income tax deductions.

While the six-year rule protects you from capital gains tax on sale, it does not affect your obligation to declare rental income and claim deductions during the rental period. You still report the rent received as assessable income. You still claim deductions for interest, management fees, maintenance, depreciation, and other eligible expenses.

This creates an interesting planning opportunity. During the rental period, you benefit from tax deductions that reduce your assessable income (particularly interest deductions if the property is negatively geared or depreciation deductions on the building and fixtures). When you sell, you benefit from the CGT exemption that eliminates the capital gain.

In effect, you get the best of both worlds: the tax deduction benefits of an investment property during the holding period, and the CGT exemption benefits of a main residence at the point of sale.

This dual benefit is one of the most powerful features of the six-year rule, and it is the aspect that most accountants fail to highlight proactively. They will process your rental income return correctly. They will calculate your depreciation schedule. But many will not actively suggest that you plan your property moves around the six-year clock to maximise the CGT exemption.

Our role as buyer's agents extends beyond the purchase. We flag the six-year rule during initial strategy sessions for any client who currently lives in a property they may convert to a rental. The tax planning conversation happens before the purchase decision, not after. Because once you have bought a second property and moved out of the first, the clock is already ticking.

## The Traps You Must Avoid

Trap one: claiming two main residences simultaneously. You cannot claim the six-year exemption on your old home while also claiming your new home as a main residence, unless you follow the specific overlap rules for a reasonable changeover period. The ATO allows a brief overlap when transitioning between homes, but claiming full exemption on both properties simultaneously will trigger audit attention.

Trap two: exceeding six years without resetting. If you rent out the property for seven years without moving back in, you lose the exemption for the entire period beyond six years, not just the seventh year. The ATO will apportion the exemption based on the ratio of exempt to non-exempt periods.

Trap three: insufficient evidence of genuine residence. When you move back in to reset the clock, you need to actually live there. Update your electoral roll. Redirect your mail. Connect utilities in your name. Store your personal belongings there. The ATO will examine all of these indicators if your exemption claim is audited.

Trap four: foreign residents. If you become a foreign resident for tax purposes, the main residence exemption may be denied entirely under the foreign resident CGT rules introduced in 2017. This is particularly relevant for expatriates who lose their Australian tax residency while working overseas.

I always recommend clients get specific advice from a property-specialist tax accountant. The six-year rule is powerful, but the interactions with other tax provisions can be complex. Our role is to flag the opportunity. Implementing it correctly requires professional tax guidance.

## Why This Matters for Your Investment Strategy

The six-year rule is not just a tax minimisation tool. It is a strategic planning instrument that should influence when you buy, when you move, and how you structure your property portfolio.

If you know the rule exists, you can plan around it. You can time your property moves to maximise the exemption period. You can structure your portfolio so that your highest-growth property benefits from the main residence exemption. You can avoid triggering unnecessary CGT events by understanding the clock and managing it actively.

David, the IT manager I mentioned at the start, saved $127,000 by understanding how the clock worked and restructuring his plans accordingly. That is not a marginal saving. That is more than the deposit on another investment property.

The rule was always there. The ATO published it. The legislation is publicly available. But most homeowners do not know it exists, and many accountants do not proactively raise it unless asked.

Now you know. Use it.

I also want to highlight a less-discussed application of the six-year rule that is relevant to investors with multiple properties: the main residence nomination strategy.

Under Australian tax law, you can only nominate one property as your main residence at any given time. But the choice of which property to nominate is strategic, not automatic.

Consider an investor who owns three properties. Property A was purchased in 2015 for $500,000 and is now worth $900,000 (gain: $400,000). Property B was purchased in 2017 for $600,000 and is now worth $800,000 (gain: $200,000). Property C was purchased in 2020 for $700,000 and is now worth $750,000 (gain: $50,000).

If the investor needs to sell one property, which one benefits most from the main residence exemption? Property A, with the largest gain. By nominating Property A as the main residence (assuming they lived in it at some point and it qualifies under the six-year rule), they exempt $400,000 from CGT. At a marginal rate of 37% with the 50% discount, that saves approximately $74,000.

If they had nominated Property C as their main residence instead, the exemption would save only $9,250 (37% x 50% x $50,000). The difference in tax outcome: $64,750. From the same rule, applied to different properties.

This is why I say the six-year rule is not just a tax minimisation tool but a strategic planning instrument. The nomination decision should be made proactively, based on projected future gains, not reactively at the point of sale. Get this wrong and you could pay $65,000 more tax than necessary. Get it right and you have funded a deposit on your next property.

We raise this during strategy sessions with every client who owns or has owned a main residence. The earlier the planning begins, the more options remain available.

## References

1. [ATO Section 118-145 ITAA 1997: absence from main residence, six-year CGT exemption rule.](https://www.ato.gov.au/individuals/capital-gains-tax/property-and-capital-gains-tax/your-main-residence/)
2. [ATO Community forum: guidance on re-establishing main residence to reset six-year period.](https://community.ato.gov.au/)
3. [ClearTax Australia: practical guide to the six-year CGT absence rule with worked examples.](#)
4. [DuoTax: main residence CGT exemption calculator and scenario modelling.](#)
5. [Trove Group: capital gains tax planning for property investors, six-year rule analysis.](#)
6. [ATO foreign resident CGT rules: 2017 amendments removing main residence exemption for non-residents.](https://www.ato.gov.au/individuals/capital-gains-tax/property-and-capital-gains-tax/foreign-residents/)
7. [H&R Block Australia: common mistakes when applying the main residence CGT exemption.](https://www.hrblock.com.au/)
8. [ATO audit indicators: evidence requirements for main residence claims including electoral roll and utility records.](https://www.ato.gov.au/)
9. [CoreLogic median house price growth data: Melbourne, annual and rolling five-year periods.](https://www.corelogic.com.au/research/)
10. [PremiumRea client consultation data: six-year rule advisory as part of property strategy planning.](#)

---

Source: https://premiumrea.com.au/blog/six-year-rule-capital-gains-tax-exemption-investment-property
Publisher: PremiumRea (Optima Real Estate) — Melbourne buyers agent