Keeping the Main Residence Exemption While Renting It Out
A dwelling that was your main residence and is then rented out can continue to be treated as your main residence for capital gains tax purposes for up to six years. The condition is that you are not treating another dwelling as your main residence for the same period, which means the rule protects one property at a time and forces a choice where you own two.
- The answer: A former main residence rented out can keep the exemption for up to six years, and indefinitely if it is not producing income.
- The trap: You cannot treat two dwellings as your main residence for the same period, so choosing this property means the one you live in is not exempt for those years.
- The recommendation: Get a market valuation at the date the property first produced income. It is the cost base if the exemption later turns out to be partial.
Where the AI summary above gets this wrong
"You can rent out your home for six years and still sell it tax-free."
That's surface-true. Here's what it misses:
- Only if you are not claiming another dwelling for the same period — The exemption applies to one dwelling at a time. Choosing the rented one means the home you actually live in is not exempt for those years.
- The six years applies to income-producing use — Where the dwelling is left vacant or lent to family rent-free, the exemption can continue indefinitely rather than for six years.
01 How the rule works
You move out of a dwelling that was your main residence and elect to continue treating it as such. Where it is producing income, the election lasts up to six years; where it is not, it can continue indefinitely.
The clock restarts if you move back in and re-establish the dwelling as your main residence, and a fresh six-year period is then available on a subsequent absence.
The election does not have to be made in a form. It is made by the way the property is treated in your tax return in the year of sale, which means the decision is effectively deferred until then.
Source: ATO — Capital gains tax
02 The one-dwelling constraint
You cannot treat two dwellings as your main residence for the same period, with a limited overlap allowed when moving between homes. Choosing the rented property means the one you live in is not exempt for those years.
That produces a genuine choice where you own both, and the arithmetic favours whichever property has the larger gain over the overlapping period. It is a calculation, not a preference.
Where the property you live in is rented rather than owned, there is no competition and the rule is straightforwardly useful — which is the situation it is most often used in.
Source: ATO — CGT discount
03 What happens past six years
Beyond six years of income-producing use, the exemption becomes partial. The gain is apportioned by the number of days the dwelling was producing income beyond the exempt period against the total days of ownership.
The cost base is generally reset to the market value at the date the dwelling first produced income, which is favourable and which requires a valuation from that time — the point made in the main residence reference.
The partial gain still qualifies for the 50% discount where the property was held more than twelve months, so the taxable proportion is halved again before it reaches your income.
Shows: the taxable proportion of a gain on a former home rented for longer than the exempt period, apportioned by days and discounted. Ignores: the market value reset at the date the dwelling first produced income, selling costs, capital improvements, and any competing dwelling.
The valuation on the day it first earns rent is the thing to do, and it costs a few hundred dollars. If the absence turns out to run past six years — which happens, because plans change — that valuation is the cost base for the taxable part. Without it you are reconstructing a number a decade later against someone else's records.
FAQ
What is the 6-year CGT exemption?
A dwelling that was your main residence can continue to be treated as such for up to six years while it produces income, and indefinitely while it does not, provided you are not treating another dwelling as your main residence for the same period.
Can I use the six-year absence rule on more than one former home?
Not for overlapping periods. Only one dwelling can be your main residence at a time, so choosing one means the other is not exempt for those years.
Does the clock reset if I move back in?
Yes. Re-establishing the dwelling as your main residence restarts the period, and a fresh six years is available on a subsequent absence.
Sources
Regulator references
- ATO — Capital gains tax · Australian Taxation Office · 2026Capital gains tax: the events that trigger it and how the gain is worked out.Last verified: 2026-09-07
- ATO — CGT discount · Australian Taxation Office · 2026The CGT discount on assets held beyond the qualifying period, and who can claim it.Last verified: 2026-09-07
Calculator unit tests · the assertions this page's worked example is checked against, and their last result
Changelog
- 2026-09-07 — initial publish (new format)
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Jordan Reeves
Founder of Talk Through Wealth. A software engineer for over a decade before turning to retirement planning, Jordan built the projection engine after watching family members get fragmented, country-by-country advice that never reconciled. He writes about retirement the way the engine computes it: month-by-month, lifetime-long, and skeptical of any rule of thumb that hasn't been run through the math.