Free CGT calculator for property
Capital gains tax calculator: 50% discount vs indexation
Type in your figures and compare the two ways of splitting a gain across 1 July 2027. It says so when the ATO formula wins.
- Both methods side by side
- Runs in your browser only
- No sign-up
Compare both ways of splitting your capital gain
There are two ways to split a capital gain across 1 July 2027. This compares them on your own numbers, so you can see whether paying for a recorded market value would leave you better off - or whether the ATO formula already does.
ATO time-apportionment method
Estimates the value at 1 July 2027 as if the property grew at one steady rate from purchase to sale. No valuation needed.
Estimated CGT--
- Gain treated as pre-2027
- --
- Gain treated as post-2027
- --
Market-value method (with a recorded valuation)
Splits the gain on what the property was actually worth at 1 July 2027.
Estimated CGT--
- Gain treated as pre-2027
- --
- Gain treated as post-2027
- --
Fill in the figures above to see the comparison.
What this model assumes
- Your property moves at a flat 7% a year from what it is worth today: to 1 July 2027 (forward while that date is ahead, back once it has passed), and to the sale unless you enter your own sale price. Real growth is never flat, and the comparison is sensitive to that.
- The ATO formula follows the government exposure draft of August 2026: it assumes one steady compounding growth rate from purchase to sale and reads the value at 1 July 2027 off that curve. The draft is not final, and the formula may change.
- So the two methods only part ways when growth was uneven. A property that grew at a steady rate gets the same answer from both; one that grew faster early on does better with a recorded market value.
- The pre-2027 share of the gain is taxed on half of it at your marginal rate, which is the current 50% discount.
- The post-2027 share is taxed on the gain above the value at 1 July 2027, with that value raised by inflation, assumed at 2.5% a year. Each method uses its own value at 1 July 2027.
- A 30% minimum tax is applied to the post-2027 share, so a rate below 30% is lifted to 30% on that share. It is not applied to the pre-2027 share.
- One rate is applied to the whole gain. In a real return the gain is added to your income for the year and can span more than one bracket.
- Years are counted whole: a year you pick is read as 1 July 2027 in that year. The real formula counts days, so a purchase or sale close to 1 July 2027 can split differently.
- Ignored entirely: cost-base additions and selling costs, capital works deductions, the main-residence exemption and partial exemptions, ownership splits, and carried-forward capital losses. Properties acquired before 20 September 1985 are not modelled.
- Figures are rounded to the nearest 100 dollars.
Illustrative estimates only. Not tax, legal or financial advice. The rules described are simplified - confirm your position with your accountant.
1 July 2027 - CGT discount rules change
Gains accrued before 1 July 2027 keep the 50% discount. Splitting a gain across that date is done primarily by the property's market value on the day, or by the ATO's apportionment formula.
Counting down to 1 July 2027.
What it costs
Every report has one fixed price, and you see it in full before you pay.
Automated
Property Value Estimate Report
A fixed price, shown in full before you pay.Covers one property, paid online.
An automated estimate of what your property is worth.
- Coverage checked before you pay
- Estimated value with a confidence range
- The comparable sales the estimate is built from
- Covers addresses where sales data allows
An automated estimate, not a professional valuation.
Before 1 July 2027, this is a booking: you pay now, and the report is finalised once the date has passed.
Join the waitlistSigned by a certified practising valuer
Certified valuation
A fixed price, shown in full before you pay.Covers one property, paid online.
A valuation prepared and countersigned by a certified practising valuer, for an ATO position, an SMSF audit or a legal matter.
- Prepared and countersigned by a certified practising valuer
- The valuer's credentials are printed on the report
- Written for an auditor or the ATO to read
- Covers properties Australia-wide
Before 1 July 2027, this is a booking: you pay now, and the report is finalised once the date has passed.
Join the waitlistIf you start with the Property Value Estimate Report and order a certified valuation on the same property within 30 days, what you paid for the estimate comes off the price.