New-Build vs Established Post-Budget 2026: Does the NG Carve-Out Actually Change the Maths?

Who This Is For

The Australian property investor who has read the 12 May 2026 Federal Budget headlines, understands that the proposed framework treats new builds and established stock differently for negative gearing, and now wants to know what the difference actually is in dollar terms over a real ten-year hold. Personal-name acquisition. One investment property already owned or planning a first. Marginal tax bracket 37% or 45%.

Executive Summary — The 30-Second Read

At a Glance: The Two Properties

The short answer. New-build wins early; established wins late; the crossover sits around year 6–7. Run the maths against your own hold period before deciding.

Why This Question Matters Now

It is the third week of May 2026. The Federal Budget on 12 May proposed two reforms intended to take effect 1 July 2027: negative gearing to be quarantined on established residential stock acquired after 7:30pm AEST on 12 May 2026, and the 50% CGT discount to be replaced with cost-base indexation plus a minimum effective tax rate of 30% on the indexed net gain. The Budget papers indicate that new builds, build-to-rent, complying super funds (including SMSFs), and widely-held trusts are intended to remain outside the proposed NG restrictions. Final treatment will be confirmed in Treasury exposure drafts and the legislation that follows.

Every Australian property investor who buys between now and 1 July 2027 is making one of three bets. Bet one is that the proposed reforms become law substantially as announced. Bet two is that they are watered down materially between now and 1 July 2027. Bet three is that the policy holds long enough to matter, then a future government reverses it. Most informed investors are pricing bet one — taking the Government at its word that the policy will hold, and asking the more useful question: given these proposed rules, which Australian property pathway has the better after-tax economics?

That is the question this article answers. Not the strategic framing — we covered the strategic side in our post-Budget property investment strategies blog and the policy explainer in our budget 2026 negative gearing CGT international lessons piece. This is the numerical side: two real properties at matched $750K purchase prices, modelled year-by-year over a 10-year hold, with the after-tax results compared head-to-head.

1. The Two Policy Levers Reshaping the Maths

1.1 Negative gearing — what is proposed to change and what is indicated to stay the same

Before 12 May 2026, an Australian investor running a $15,000 paper loss on an investment property could offset that loss against their PAYG salary. At a 39% marginal rate, that loss recouped $5,850 in tax. The cashflow drag was real but tax-shielded.

Under the Government's announced framework, for established stock acquired post-7:30pm on 12 May 2026, the loss is indicated to survive but to be offsetable only against rental income (current or future, from the same investment class). It would no longer reduce taxable salary. The cash impact under the proposed framework: the investor still wears the $15,000 loss out of after-tax salary, but instead of recouping $5,850 immediately, they carry the loss forward to offset against rental income (potentially years away). In present-value terms, this turns an immediate $5,850 benefit into a delayed $5,850 benefit with discount-rate erosion.

For new builds — off-the-plan, house-and-land on vacant land, knock-down rebuilds that add dwellings — the pre-Budget rule is indicated to survive in full for the first owner. The $15,000 loss would continue to offset salary in the year it is incurred, with the $5,850 recovery happening at tax-return time. The precise definition of "new build" eligibility, the carry-forward loss bank mechanics, and the treatment of mixed-use additions all sit in the exposure draft legislation that has not yet been released.

1.2 CGT — the proposed mechanics in precise terms

The proposed CGT change applies symmetrically to both property types. Three mechanics matter and they often get conflated in commentary:

1. Cost-base indexation. The acquisition cost base grows with inflation (CPI), measured from acquisition date to disposal date. A $750,000 purchase that survives 10 years of 3% inflation has an indexed cost base of $750,000 × (1.03)¹⁰ = $1,008,000. Only the gain above the indexed cost base is taxable. This replaces the prior 50% discount mechanism.
2. Inclusion in assessable income. The indexed net gain is added to assessable income in the year of disposal. It is taxed at the investor's marginal rate — not at a flat rate. Under the existing 50% discount regime, only half the nominal gain was assessable. Under the proposed regime, the full indexed gain is assessable.
3. The "30% minimum" floor. Where the investor's marginal tax rate would otherwise apply less than 30% to the indexed gain (because of bracket structure, deductions, or other offsets), an effective floor of 30% applies. In practical terms: for investors at the 39% or 45% marginal rate, the 30% floor is not binding — their actual rate on the indexed gain is already above 30%. The floor binds only for lower-bracket investors, charity-owned vehicles, or structures where the effective rate would otherwise fall below 30%.

This matters because the headline framing "30% CGT rate" is misleading. For typical high-bracket investors, the change is actually about moving from a 50% discount on nominal gain to taxing the indexed gain at full marginal rates. Depending on hold period and nominal growth, that can be more or less generous than the prior regime — see Section 6 for a worked example. The proposed change is indicated to apply to all CGT assets disposed of after 1 July 2027 — except those acquired or under contract before 7:30pm on 12 May 2026, which are indicated as grandfathered into the existing 50% discount regime for the entire hold.

1.3 The depreciation difference (which predates the Budget)

Depreciation rules did not change at the 2026 Budget. But they meaningfully amplify the new-build advantage for one reason: the 2017 second-hand plant rule still applies. An investor buying an established property cannot claim Div 40 (plant and equipment) on items the previous owner installed. A new-build buyer claims Div 40 in full on everything installed by the developer.

Combined with Div 43 (capital works at 2.5% of construction cost over 40 years), the new-build typically out-depreciates the established by $8,000–$12,000 a year for the first 5–8 years. At a 39% marginal rate, that is $3,100–$4,700 per year in cash-equivalent tax shield — most of which is depreciation timing rather than a permanent tax saving, but timing matters. The new-build vs established gap is therefore the sum of two effects: the post-Budget NG carve-out (a permanent tax-timing benefit on losses) plus the existing depreciation gap (a temporary tax-timing benefit on phantom expenses). The case studies below combine both.

2. Property A: Adelaide Outer-North Established House ($750K)

Salisbury, SA. 1985-built three-bed house on a 600m² block. Gross weekly rent $840 ($43,680 pa), gross yield 5.82%. Vacancy 4%, property management 8.8% inc GST, council/insurance/maintenance $5,200 pa. We have referenced Salisbury, Elizabeth and Munno Para as Adelaide yield plays in our post-Budget strategy piece; sub-1% vacancy and 5.5–6.2% gross yields make 5.82% realistic, not aggressive.

2.1 Finance structure

• Loan amount: $675,000 (90% LVR)
• Loan type: P&I, 30-year term, investor variable
• Modelled rate: 6.95% (mid-range investor variable as of May 2026)
• Year 1 interest expense: ~$46,500
• Year 1 principal repayment: ~$7,200
• Loan establishment + LMI: $14,500 (capitalised)

Acquisition costs (separate from loan): stamp duty $34,500, legals and inspections $2,800, buyers' agent fee $9,000, finance arrangement $1,500. Total acquisition costs ~$47,800. Combined with the deposit ($75,000) and capitalised LMI, total cash-in at settlement is roughly $137,300.

2.2 Year 1 income and expense

2.3 Year 1 cash position

Year 1 pre-tax cash outflow: rent $41,933 received, minus all cash outgoings (mgmt, rates, insurance, full P&I repayment $53,700) = $41,933 − $62,590 = −$20,657 cash drag before tax.

Tax treatment under the post-Budget regime: the $15,957 loss is quarantined. It cannot reduce salary tax. It carries forward to offset future rental income from the same investment class. Year-one tax refund from this loss: $0. Net year-1 after-tax cash position: −$20,657.

Under the pre-Budget regime (or if the property were grandfathered), the $15,957 loss would offset salary at the 39% marginal rate, recovering $6,223 of tax. Pre-Budget net year-1 after-tax cash position: −$14,434. The 2026 Budget therefore costs the Property A buyer ~$6,200 in year-1 after-tax cashflow.

2.4 Capital growth trajectory

We model Adelaide outer-north at 5.0% per annum nominal capital growth. This is below the 7–9% the same suburbs delivered through 2023–25 and above the 3% inflation rate — a deliberately middle-of-the-road assumption. The land component in Salisbury houses sits at roughly 65–70% of total value, which is why land-driven growth dominates the trajectory. At 5.0% pa, $750,000 compounds to $1,221,000 by end of year 10. Headline capital gain: $471,000.

2.5 The carry-forward loss bank

The quarantined losses do not disappear — they build year by year as a rental loss bank that can be used against future rental income. By year 10, with losses tapering toward zero as rent grows and interest falls, the loss bank plausibly holds $40,000–$70,000 of accumulated deductions. If the property is held past year 10 and rent exceeds expenses, the loss bank starts to be drawn down. The PV cost of this deferral, at a 6% real discount rate, is roughly 30–40% of the nominal recovery. The Budget therefore does not destroy the tax shelter — it delays it. The practical impact for a 10-year hold is closer to "lose $0.30–$0.40 on every dollar of NG benefit you would have received pre-Budget" than to "lose the entire benefit."

3. Property B: Brisbane New-Build Townhouse ($750K)

Brisbane Olympic corridor. 2026-completed three-bed townhouse, body-corporate scheme ($3,400 pa strata). Gross weekly rent $755 ($39,260 pa), gross yield 5.23%. Newer stock typically prices at lower yields because body-corp drag and depreciation tax shield make headline yield misleading. Referenced previously in our Brisbane 2032 Olympics property investment and Brisbane property investment trends 2026 pieces.

3.1 Finance structure

Identical loan structure to Property A: 90% LVR, $675,000 loan, 6.95% investor variable, P&I. Year-1 interest ~$46,500 and principal ~$7,200 — same as Property A.

Acquisition costs differ. Stamp duty on a new build in Queensland is calculated on land value rather than total purchase price in some product types (off-the-plan / house-and-land), so the duty bill can be materially lower — modelled here at $19,500 instead of Property A's $34,500. Some product types attract first-investor concessions which we have not modelled. Total acquisition costs ~$33,300. Combined with deposit and capitalised LMI, total cash-in at settlement is roughly $122,800 — about $14,500 less than Property A.

3.2 Year 1 income and expense

3.3 Year 1 cash position

Year 1 pre-tax cash outflow: $37,690 effective rent − $62,817 cash outgoings (mgmt + strata + council/insurance + P&I) = −$25,127 cash drag before tax — worse than Property A because the body corporate exceeds A's council/insurance/maintenance. Under the proposed framework, NG carve-out preserved: $31,327 tax loss × 39% = $12,217 tax recovered. Net year-1 after-tax: −$12,910. The new-build is ~$7,750 better year-1 after-tax than Property A, despite worse pre-tax cashflow — the entire delta sits in the tax shield, and most of that shield is depreciation, not the NG carve-out.

3.4 Capital growth trajectory

We model the Brisbane new-build at 3.5% per annum nominal capital growth. This is below the 6–8% historical Brisbane established benchmark and is the conservative end of what data centres, the Olympic corridor and population growth could support. The reason for the lower assumption: a new-build townhouse has a higher building-to-land ratio than a 600m² Adelaide block, and the building component depreciates while only the land appreciates. The combined effect is a structural drag of 1.5–2.0 percentage points relative to land-rich established stock. At 3.5% pa, $750,000 compounds to $1,058,000 by end of year 10. Headline capital gain: $308,000. The gap to Property A's $471,000 gain is $163,000.

4. Side-by-Side Year-1 Cashflow

The clearest comparison is the head-to-head year-one position.

Property B is $7,747 better off year-1 after tax despite generating $4,243 less rent. The mechanism: depreciation lets it report a tax loss far larger than its actual cash loss; the NG carve-out lets that tax loss be used immediately rather than carried forward.

4.1 Tax bracket sensitivity

The new-build advantage scales with marginal tax rate. Three cases:

Maximum benefit accrues to 39–45% bracket investors — exactly the cohort the NG reform was politically designed to limit. The proposed framework therefore both targets high-bracket investors (by quarantining established-stock NG) and simultaneously rewards them for redirecting capital to new builds (by preserving NG on new stock). Whether that policy outcome was intentional is a separate question — but the mathematics is unambiguous.

5. Ten-Year Cumulative Cashflow + Capital Growth

A single year says little. The hold-period view is where the comparison resolves.

5.0 Why the cap-growth gap is set at 5.0% vs 3.5% — assumption sourcing

The capital growth differential between Property A (Adelaide outer-north house at 5.0% pa) and Property B (Brisbane new-build townhouse at 3.5% pa) is the single largest driver of the 10-year result. It is also the assumption most exposed to challenge. Four data threads support the 1.5 percentage-point gap.

1. Land-to-asset ratio. Cotality and PropTrack valuation models consistently show land component as the dominant driver of long-run capital growth. A detached house on 600m² in Salisbury sits at roughly 65–70% land value as a share of total purchase price. A new-build townhouse on a body-corporate scheme sits at 30–40% land value. Land appreciates; building components depreciate. The land-component gap alone produces a structural 1.5–2.0 percentage point spread in long-run growth, independent of location or cycle.

2. Historical detached-vs-townhouse spread. Cotality's Home Value Index series (running back to 2004) shows a persistent ~150–200 basis point annual spread between detached houses and attached dwellings (units and townhouses) in the four largest capitals over rolling 10-year windows. The spread narrows in supply-constrained inner-city cycles and widens in outer-suburban land releases — but is consistently positive for houses.

3. Brisbane Olympic corridor specifics. Brisbane new-build townhouse stock in the Olympic corridor benefits from infrastructure tailwinds but faces material supply elasticity (more on this in Section 8.7). HIA forecasts and PropTrack new-dwelling completion data both point to elevated supply through 2027–28 as the Olympics pipeline matures. 3.5% pa is at the upper end of what a supply-elastic new-build segment typically delivers, not the lower end.

4. Adelaide outer-north specifics. Salisbury, Elizabeth and Munno Para have delivered 7–9% pa nominal growth through 2023–25 on Cotality data, well above the 5.0% modelled. Defence anchors (Edinburgh RAAF base, ASC submarine program), advanced manufacturing, and lifestyle migration from Melbourne underpin a structural demand floor. 5.0% pa is a deliberately conservative middle-of-the-road assumption that understates recent performance to avoid criticism of cherry-picking.

5.1 Assumptions for the 10-year run

• Rent growth: 4.0% per annum nominal (both properties)
• Interest rate: 6.95% in years 1–3, falls 50bps in year 4, falls another 50bps in year 6, then flat. Final-year rate 5.95%.
• Property expenses (rates, strata, insurance) inflate at 3.0% per annum
• Capital growth: 5.0% pa Property A, 3.5% pa Property B
• Investor marginal tax rate: 39% throughout
• Loss carry-forward (Property A): builds in years 1–6, drawn down in years 7–10 as rent exceeds expenses

5.2 Cumulative after-tax cashflow over 10 years

Property B is $20,447 ahead on cumulative after-tax cashflow over the 10-year hold. This is the cashflow-only view, before any consideration of capital growth.

5.3 The crossover dynamic

Property B is ahead every year from year 1 through year 6. Property A catches up in years 7–10 as the loss bank deploys and rent growth overtakes interest decline. By year 10, Property A's annual after-tax cashflow is ahead of Property B's and the gap is widening. The trade-off: Property B front-loads the benefit; Property A back-loads it.

5.4 Add capital growth and the result inverts

• Property A end-of-year-10 equity: $1,221,000 − $568,000 loan balance = $653,000
• Property B end-of-year-10 equity: $1,058,000 − $568,000 loan balance = $490,000
• Cumulative after-tax cashflow drag for Property A: ($37,357)
• Cumulative after-tax cashflow drag for Property B: ($16,910)

Net equity position year 10 (equity minus cashflow drag):

• Property A: $653,000 − $37,357 = $615,643
• Property B: $490,000 − $16,910 = $473,090

Property A is $142,553 ahead on net wealth at year 10. The 1.5 percentage-point capital-growth gap, compounding over 10 years on a $750K base, produces a $163,000 capital-gain advantage that more than offsets Property B's $20,447 cashflow advantage by a factor of seven.

6. After-Tax IRR Over the 10-Year Hold

Cashflow tables tell one story; IRR tells the more useful one.

6.1 IRR calculation

Cash flows: year 0 deposit + acquisition costs, years 1–10 net after-tax cashflows, year 10 sale proceeds net of CGT and 2.5% selling costs. Indexed cost base after 10 years at 3% inflation: $750,000 × (1.03)¹⁰ = $1,008,000.

• Property A: indexed gain $213,000, CGT at 30% = $63,900, net sale proceeds $1,126,575, less loan payoff $568,000 = $558,575 net to investor.
• Property B: indexed gain $50,000, CGT at 30% = $15,000, net sale proceeds $1,016,550, less loan payoff $568,000 = $448,550 net to investor.

6.2 IRR comparison

• Property A IRR over 10 years: approximately 9.1% pa after tax
• Property B IRR over 10 years: approximately 7.6% pa after tax

Property A wins on IRR by ~1.5 percentage points. The lower CGT bill on Property B (because of lower nominal gain) is genuinely valuable — but does not close the gap created by the capital-growth differential and the cumulative compounding effect.

6.3 The CGT sub-story

A counterintuitive result is buried in the CGT line: Property B has lower CGT because it has lower nominal gain. Under the old 50% discount regime, Property A would have paid CGT of $471,000 × 50% × 39% = $91,845. Under the new regime it pays $63,900 — actually lower, because indexation strips out the inflation component that the 50% discount used to handle indirectly. The headline "30% minimum is worse than 50% discount" is misleading for typical 10-year holds on land-rich assets; the new regime can be more or less generous than the prior one depending on hold period and nominal growth rate.

7. Sensitivity: What Breaks the Established Advantage?

Three assumptions, if they move, can flip the result.

7.1 Capital growth differential

If Adelaide outer-north delivers only 3.5% pa (matching new-build), the capital-gain gap closes and Property B leads by ~$15,000 at year 10. Plausibility: low. Adelaide outer-north delivered 7–9% pa through 2023–25 and structural drivers (defence, advanced manufacturing, 0.7% vacancy) have not weakened. If the Brisbane new-build delivers 5.0% pa (matching A), the gap also closes — plausibility: moderate in narrow infrastructure-led corridors.

7.2 Hold period

Under 5 years → Property B wins outright (cashflow advantage compounds before cap-growth dominates). 10+ years → Property A wins decisively (the 1.5-point gap is a steamroller after year 8). 6–7 years → too close to call; cashflow tolerance decides.

7.3 Interest rate trajectory

Rates flat at 6.95% (no cuts): both worsen, A worsens more in absolute terms but A still wins on net equity by $130K+. Faster cuts (year 2 instead of year 4): A benefits more because loss-bank deployment starts earlier. Implication: NG carve-out value to new-builds is highest in higher-rate environments and compresses as rates normalise.

7.4 Bracket creep

Income above $190K (47% bracket) → B advantage widens. Income below $135K (32.5%) → B advantage compresses. High-income earners benefit disproportionately from new-builds; low-income earners from established yield. Breakpoint ~37%/39% threshold.

7.5 Policy reversal

A future reversal of the NG change before sale gives Property A a refundable benefit on its $40–70K accumulated loss bank, deployable against salary in the reversal year. NG reform has a fragile political history — holding Property A is implicitly long-volatility on policy reversal.

7.6 Rent growth sensitivity

The 4% nominal rent growth used in the base case is reasonable given current 7.3% YoY asking-rent growth (per SQM April 2026 data) and a structural easing back toward long-run averages over the hold period. The table below tests three rent-growth assumptions against the cumulative 10-year after-tax cashflow result.

At 2.0% rent growth — a deliberately conservative downside — Property A's net equity at year 10 falls by $32,000 vs the base case. Property B's falls by $28,000. The gap between A and B widens slightly under low-rent-growth assumptions. The case-study conclusion is not sensitive to rent growth assumptions. It is sensitive to capital growth assumptions (Section 5.0).

7.7 Real vs nominal returns — inflation-adjusted view

The case-study modelling reports nominal results throughout. Under the proposed CGT regime, cost-base indexation makes real-returns analysis more relevant than under the prior 50% discount regime. At 3% assumed inflation over the 10-year hold, the real (CPI-adjusted) results compress as follows:

In real terms, Property B's capital gain over 10 years compresses to roughly $37,000 — close to zero in inflation-adjusted terms. This is the structural cost of buying a building-component-heavy asset. Property A's real gain at $158,000 is still meaningfully positive, reflecting the land-component appreciation above inflation. Investors evaluating these two pathways should reframe the question: is the goal to preserve real purchasing power (in which case Property A is materially better positioned) or to maximise nominal cashflow during the hold (in which case Property B has the edge)?

8. When Established Still Wins (and How to Identify It)

The case-study modelling resolves to "established wins on 10-year IRR" — but that result is conditional on the established asset being genuinely land-rich, in a genuine growth corridor, and held long enough for compounding to dominate. Three filters separate established-stock that will outperform from established-stock that will not.

8.1 The 65% land-component rule

Established stock where land value is at least 65% of total purchase price will deliver land-driven compounding. Anything below 50% land component loses its structural advantage and behaves more like new-build stock on growth. Adelaide outer-north houses sit at 65–70% land. Sydney inner-city units sit at 25–35% land.

8.2 Vacancy < 1.5%

Tight rental markets compress the cashflow drag because rent growth runs faster than expense growth. Adelaide outer-north at 0.7% vacancy supports the 4% rent growth assumption in the modelling. Markets with vacancy above 2.5% will not deliver 4% rent growth, and the cashflow drag in years 1–6 widens enough to materially erode the IRR.

8.3 Cashflow-positive on day one

Genuinely cashflow-positive established stock — properties where rent exceeds all expenses including interest — sees zero benefit from the NG carve-out because there is no loss to deduct. For this cohort, the post-Budget regime is irrelevant. We covered the candidate markets in our regional property investment australia 2026 and top rental yield suburbs australia 2025 pieces.

8.5 State-by-State Stamp Duty: The Other Asymmetry

The case-study modelling used a single Adelaide vs Brisbane comparison. Stamp duty differs materially across states, and several states have new-build concessions that the modelling did not fully capture.

Established stamp duty on $750K (investor, no concessions)

New-build stamp duty on $750K (off-the-plan or H&L)

Largest stamp-duty asymmetry sits in Victoria (OTP above construction stage saves $15–20K). NSW and SA savings are modest. State choice matters as much as new-build vs established — two new-builds at the same price in different states can produce IRRs that differ by 1–2 percentage points purely from stamp duty asymmetry.

8.6 What the Modelling Does Not Capture

Five real-world factors sit outside the case-study modelling but affect the actual outcome.

8.6.1 Defect risk on new builds

A meaningful share of post-2018 apartment and townhouse stock has presented with structural, fire-safety, or waterproofing defects discovered after settlement. The NSW Building Commissioner has flagged defects in roughly 40% of audited mid-rise residential strata buildings. Defect remediation can cost $20,000–$80,000 per unit in special levies. The modelling assumed zero defect cost on Property B. The honest range: a 15–25% probability of $10,000–$40,000 of unbudgeted defect cost over the 10-year hold.

8.6.2 Body-corp escalation on new builds

Body-corp fees on new strata schemes typically grow faster than CPI in years 5–10 as the sinking fund recapitalises for capital works. A $3,400 year-1 strata fee can grow to $5,500–$7,500 by year 10 — well above the 3% expense growth modelled.

8.6.3 Renovation upside on established

Modelling excluded renovation on Property A. A typical 1980s Adelaide outer-north house supports a $40,000–$60,000 cosmetic renovation delivering 1.5–2.5× return in valuation uplift plus 10–15% rent uplift — a $50,000–$100,000 equity lever available only on the established pathway. Strategic renovation widens the IRR gap by another 1–2 percentage points.

8.6.4 Lender preference shifts and OTP financing repricing

Off-the-plan settlements depend on the lender's valuation at settlement matching the contract price agreed 12–24 months earlier. In falling markets, this gap forces the buyer to top up the deposit, refinance at worse terms, or walk away (forfeiting deposit). The 2024–25 period saw widespread OTP shortfalls in inner-Sydney and inner-Brisbane apartment stock; the post-Budget price softness flagged in our PropTrack April 2026 analysis raises this risk again.

A second OTP financing risk is rate repricing between contract and settlement. The investor variable rate modelled at 6.95% reflects May 2026 pricing. If rates move 50–100bps higher between contract and settlement on a 24-month off-the-plan timeline, the year-1 interest cost rises by $3,000–$7,000 and the marginal serviceability gap widens. Pre-approvals expire; re-approval at the new rate may fail. This risk is asymmetric: an established settlement closes within 60 days at current rates, while an OTP settlement is structurally exposed to interim rate movement.

8.6.5 Builder insolvency, sunset clauses, and completion risk

Builder insolvency. ABS data on construction industry insolvencies has run elevated through 2023–25. The collapse of a builder mid-project can leave a deposit at risk (depending on Home Warranty Insurance limits, which vary by state) and the project either abandoned, taken over by an administrator-appointed builder, or substantially delayed. A 5–10% historical incidence rate on mid-rise residential projects means this is not a tail risk — it is a present-cycle reality.

Sunset clauses. OTP contracts typically include a sunset date — usually 24–36 months from contract — beyond which either party can terminate without penalty. Developers in falling markets have used sunset clauses to terminate contracts on units that have appreciated above the contract price, then resold at the higher price. NSW and Victoria have legislated against this practice in recent years, but enforcement remains imperfect.

Completion risk. Even where the builder remains solvent, completion delays of 6–18 months past the original target are routine. Each month of delay extends the period during which the buyer pays interest on the land deposit (if H&L) or on the deposit bond financing (if OTP), without generating rental income. Modelled cash drag for 6 months of delay: $8,000–$15,000. A risk-adjusted Property B IRR would lower the headline 7.6% to roughly 6.5–7.0% to reflect a probability-weighted view of these construction risks.

8.6.6 Policy revision risk

The Budget framework will be drafted into legislation between now and 1 July 2027. The grandfathering details, the precise definition of "new build" eligibility, the carry-forward loss bank rules, and the cost-base indexation methodology all sit in the drafting that has not yet been released. Substantive changes — particularly to the new-build definition or the carry-forward mechanism — could materially shift the modelled result. Investors making 10-year decisions in May 2026 are pricing a policy framework that does not yet exist in statute.

8.7 Supply Elasticity: Why Land Compounds and Buildings Don't

A short economics point underpins the entire 1.5-percentage-point capital-growth gap, and it deserves explicit treatment.

Supply elasticity measures how much new supply enters the market in response to a 1% rise in price. Highly elastic supply means producers can rapidly add new units; inelastic supply means new units enter slowly and at increasing marginal cost.

Land in established suburbs is structurally inelastic. Salisbury, Elizabeth and Munno Para were subdivided decades ago. The amount of residentially-zoned land in those suburbs is fixed. Population growth, household formation, and demographic flow into Adelaide all pressure that fixed land base, and the equilibrium response is price growth — not new supply. The same logic applies to land in any established inner or middle-ring suburb where rezoning is constrained.

New-build dwelling supply is structurally elastic. Brisbane's Olympic corridor, like every growth corridor in every Australian capital, has thousands of hectares of land at various stages of development. Townhouse and apartment yields per hectare are 4–8× those of detached housing. When prices rise in the corridor, developers can — and do — release additional supply within 12–24 months. This dampens price growth at the margin and prevents the kind of land-driven compounding that established suburbs exhibit.

The implication: a $750,000 Salisbury house is buying a share of a fixed asset (land) plus a depreciating asset (building). A $750,000 Brisbane new-build townhouse is buying a share of a near-zero-elasticity attached dwelling on a small land share. Over a 10-year hold, the fixed-asset component dominates price formation. For investors with a 10-year horizon, the supply elasticity question is more important than the tax-treatment question.

9. Decision Framework

Five questions that resolve the new-build vs established choice for the post-Budget environment.

1. How long can you genuinely hold? Under 6 years → new-build. Over 8 years → established (if land-rich). 6–8 years → personal cashflow tolerance decides.
2. What is your marginal tax bracket today and projected over the hold? 39%+ and stable or rising → new-build advantage maximised. 32.5% or falling → established advantage maximised.
3. Can you absorb a $20,000+ pa cashflow drag in years 1–4 without distress? Yes → established is on the table. No → new-build, or yield-first established (which has minimal drag).
4. Is the established asset land-rich (65%+ land component) and in a sub-1.5% vacancy market? Yes → established viable. No → new-build is structurally safer.
5. What is your view on policy stability? High confidence the NG reform holds → both pathways viable as modelled. Low confidence (expect reversal) → established becomes attractive as an implicit long-option on reversal.

The honest summary: the 2026 Budget does not destroy established-property investment. It modestly handicaps it (~$3,000–$5,000 per year in deferred tax benefit) in a way that does not change the underlying capital-growth maths. For investors with the hold period and the land-rich asset, established still wins on 10-year IRR. The Budget does widen the new-build's appeal for shorter-hold and higher-bracket investors. But the new-build is winning a smaller race — early-cycle cashflow — at the cost of long-run wealth accumulation.

10. Execution Checklist

A condensed execution checklist for the post-Budget environment.

Pre-purchase: Confirm marginal tax bracket with your accountant; pre-approve finance through two lenders (one off-the-plan-friendly if pursuing new-build); order a quantity-surveyor depreciation estimate ($400–$600); re-run the case-study modelling against your actual income.

Contract stage: For post-12-May established acquisitions, ensure the accountant opens a rental-loss carry-forward tracking position from settlement. For OTP, request the developer's prior-stage defect remediation history and confirm state stamp-duty treatment in writing with your conveyancer. For OTP, use a deposit bond where available to preserve cash for offset.

Post-settlement: Engage the QS for the formal depreciation schedule before the first tax-return year-end. Set up offset/redraw to maximise deductible debt — this matters more for quarantined established stock because the salary-offset cushion is gone. Track loss bank separately by property class. Diarise rental review (months 6, 12), depreciation refresh (year 5), refinance review (years 2, 4), and sale-vs-hold review (year 7).

11. Direct Answers to Common Questions

Is a new build better than established property after Budget 2026?

Not universally. Based on the modelling in this article, new builds are better for investors with hold periods under 6 years, higher marginal tax brackets (39%+), and lower cashflow tolerance. Established stock is better for investors with hold periods of 8+ years who can absorb $20,000+ pa cashflow drag in the early years and who select land-rich assets (65%+ land component) in tight-vacancy markets.

How much is the negative gearing carve-out worth?

Under the Government's proposed framework, the carve-out's cash value is approximately the marginal tax rate × the annual property loss, as a cash-timing benefit. For a property running a $10,000 annual loss at a 39% marginal tax rate, that is ~$3,900 per year. For a $15,000 loss at 45%, ~$6,750 per year. For cashflow-positive established stock with no loss to deduct, the carve-out is worth zero.

Do new builds outperform established property after tax?

In the case-study modelling, new builds outperform established on after-tax cashflow in years 1–6, by a cumulative ~$20,000 across the full 10 years. Established outperforms new builds on capital growth by ~$163,000 over the same period. On combined after-tax net wealth at year 10, established wins by ~$142,500 at matched $750,000 purchase prices.

Which property type has the better 10-year IRR?

The modelled 10-year after-tax IRR is approximately 9.1% pa for the Adelaide outer-north established house and 7.6% pa for the Brisbane new-build townhouse. The 1.5 percentage-point IRR gap is driven by capital growth differential (1.5 percentage points pa) compounding across the hold.

Does the post-Budget regime apply to SMSFs?

The Budget papers indicate that complying super funds, including SMSFs, are intended to remain outside the proposed negative gearing restrictions. The more pressing SMSF policy change is Division 296, which commences 1 July 2026 and is covered in our SMSF Division 296 property action guide.

What is grandfathered for established property?

The Government has indicated that properties owned, or under exchanged contract, before 7:30pm AEST on 12 May 2026 will retain the existing negative gearing and 50% CGT discount treatment for the entire hold. Grandfathering is indicated to be one-time and non-transferable.

What counts as a "new build" under the proposed framework?

Based on the announced policy direction, new builds include off-the-plan apartments, knock-down rebuilds that add dwellings, and house-and-land packages on vacant land. Granny flats on existing established property are indicated not to qualify. The precise definition will be confirmed in exposure draft legislation.