Updated for the May 2026 reform
Capital Gains Tax Calculator SA
CGT is federal - South Australian sellers face the same enacted 2026 rules as everyone: the gain splits at 1 July 2027, the earlier slice keeps the 50% discount, later gains use CPI indexation plus a 30% minimum tax. The SA layer is the cost base: with no duty-free threshold on any purchase, a $650,000 buy carries $29,580 of RevenueSA duty, and every dollar of it comes off the taxable gain at sale.
- Rates verified
- 2026-08-03
- Reform
- Split at 1 Jul 2027
- Classes
- All three
The sale
= sold in FY ending 2036
CGT payable - Established (post-reform)
CPI indexation*$29,095
- Capital gain (proceeds − adjusted cost base)
- $244,070
- Taxable gain after discount/indexation/exemption
- $76,052
- Net proceeds after CGT
- $897,155
The same sale under each regime
Grandfathered
$29,095
CPI indexation
Established (post-reform)
$29,095
CPI indexation
New build
$50,706
50% discount
If CPI runs low or high - the 2-3% band
CPI 2%/yr
$46,157
+$17,062 vs assumed
CPI 2.5%/yr - assumed
$29,095
the headline figure
CPI 3%/yr
$13,889
−$15,206 vs assumed
The enacted law indexes the reset cost base by actual CPI, which no one can know in advance. Higher inflation indexes the cost base harder and lowers the taxed gain; lower inflation does the opposite. The band shown is the RBA inflation target the 2.5%/yr assumption is the midpoint of (source).
The SA costs inside this estimate
- Investor transfer duty at $650,000
- $29,580
- Conveyancing (default)
- $2,000
- Building and pest (default)
- $600
- Selling costs (default 2.5% of sale)
- $23,750
SA charges duty from the first dollar - no duty-free threshold, one scale for every buyer, computed per $100 or part thereof. None of it is deductible during the hold, so it all joins the cost base. Auto-estimated from the RevenueSA scale at the purchase price; override with your contract figures.
CGT is the last chapter of a deal. The full audit runs it against everything that came before - acquisition costs, cash flow and the quarantined loss pool it absorbs.
Deal Auditor - in build, not yet available
*The enacted law indexes cost bases by actual CPI; future CPI is unknowable, so this calculator assumes a 2.5%/yr CPI proxy (the middle of the RBA target band). The 1 Jul 2027 split defaults to a constant-growth interpolation unless you enter a valuation. Confirm the mechanics with your accountant (source). General information only.
CGT in South Australia: federal tax, SA numbers
South Australia runs the country's most unforgiving duty scale - no duty-free threshold, one scale for every buyer, duty accruing per $100 or part thereof from the first dollar - and its first home relief applies only to new builds. Capital gains tax at the other end is purely federal, but those SA choices echo through it: all that duty sits in your cost base shrinking the gain, and the new-build-only shape of SA's purchase relief mirrors the reform's own line, because first-owner new builds are also the only class that keeps the 50% discount for gains accruing after 1 July 2027. This page starts the cost base with RevenueSA investor duty at your purchase price, overridable with contract figures.
The mechanics are the national calculator's audited engine with Adelaide numbers. The gain splits at the 1 July 2027 deemed sale: the earlier slice keeps discount treatment, the later slice is CPI-indexed and carries the 30% minimum tax. Land tax paid above the indexed threshold was deductible along the way and never appears here - but for established purchases contracted after 12 May 2026, the rental losses it deepened were quarantined into a pool, and that pool offsets the gain at sale, banked slice first, exactly as the method statement orders. The regime comparison above prices all three classes on the same sale.
The SA stamp duty calculator prices the duty this page adds to your cost base on the way in. While you hold, SA land tax starts above the indexed threshold ($936,000 for 2026-27) - deductible against rent each year, never part of the cost base, with thresholds that move with average site values. And if the property was ever your home first, the SA first home buyer calculator shows the relief that only applies to new builds - and if you lived there first, those years feed the main residence exemption and the 6-year absence rule here. The national CGT calculator is this same engine without the SA defaults, and the negative gearing calculator projects the quarantined loss pool this page applies at sale.
Frequently asked questions
How is capital gains tax calculated on an investment property in South Australia?
Under federal rules, the same as every state. Proceeds after selling costs, minus the cost base: purchase price plus buying costs including RevenueSA stamp duty ($29,580 on a $650,000 purchase - SA has no duty-free threshold) and legals, less Division 43 capital works claimed. The enacted 2026 reform splits the gain at 1 July 2027: the earlier slice keeps the 50% discount, later gains use CPI indexation plus a 30% minimum tax, and the result is taxed at your marginal rate.
Is CGT different in South Australia?
No - CGT is federal. The South Australian layer is the inputs: duty from the first dollar joins the cost base (SA is one of the few jurisdictions with no duty-free threshold and no general FHB duty relief on established homes), land tax above the indexed $936,000 threshold is a deductible holding cost, and SA's new-build-only first home relief lines up neatly with the reform's new-build CGT carve-out.
Why does SA first home relief only mattering for new builds affect CGT?
Because the reform draws the same line. SA's stamp duty relief for first home buyers applies only to new homes, and federally, first-owner new builds are the one class that keeps the 50% CGT discount for gains accruing after 1 July 2027 - plus exemption from the negative gearing quarantine. A new build in SA gets relief at purchase, the discount at sale, and deductions in between; an established purchase gets none of the three. This calculator shows the sale-end difference in the regime comparison panel.
Does SA land tax reduce the capital gain?
No. SA land tax - payable above the threshold RevenueSA indexes each year, $936,000 for 2026-27 - is deductible against rental income year by year, so it never enters the cost base. For established-class purchases contracted after 12 May 2026, land tax that deepens a rental loss feeds the quarantined pool, which this calculator applies against the gain at sale before the discount step.
What did the May 2026 reform change for South Australian sellers?
For gains accruing from 1 July 2027 the 50% discount is replaced by CPI indexation plus a 30% minimum tax, for every owner - the law banks the gain to that date under the old rules via a deemed sale. First-owner new builds keep the 50% discount for later gains with a per-sale option to elect indexation. Future CPI is unknowable, so this calculator uses a labelled 2.5% a year proxy - the middle of the RBA target band.