What’s Being Proposed, What It Would Take, and What It Would Actually Change

There is renewed discussion in Canberra about changing the 50% capital gains tax discount for assets held longer than 12 months. The precise details remain unclear, but the direction of travel points toward either a reduced discount or an alternative mechanism such as partial indexation. The stated objectives are to raise government revenue and address declining housing ownership across generations.

Before reacting to the headline, it is useful to separate three questions that are often blurred together.

First, how likely is it that this change becomes law?
Second, if it does become law, what are the short and long-term effects?
Third, what is unlikely to change.

Understanding these distinctions makes the policy easier to assess without emotion.

What it takes for a CGT change to become law

A change to the CGT discount is not a discretionary adjustment. It requires legislation.

In practice, that means it must be announced in a federal budget, introduced as a bill, passed by both the House of Representatives and the Senate, and then receive Royal Assent. While the government controls the House, it does not control the Senate outright. Any reform therefore requires negotiation with minor parties and independents.

That constraint alone makes abrupt or sweeping reform less likely. It also means that design matters far more than rhetoric. Grandfathering provisions, start dates, thresholds, and transition rules ultimately determine how the policy behaves in the real world.

There is also political memory at play. CGT reform was taken to an election in 2019 and later abandoned after the loss. That history makes it unlikely that any change will be attempted without careful staging.

The most honest assessment of likelihood is simple. It is possible, but not guaranteed, and highly dependent on final design. While that uncertainty complicates forecasting, the second and third questions are more useful for planning.

What a CGT change actually targets

It is important to be clear about what this policy does and does not affect.

Capital gains tax applies only on disposal. It does not directly affect rental income. It does not reduce construction costs. It does not make land cheaper to develop. And it does not, on its own, increase housing supply.

Its primary influence is on behaviour around selling and holding.

That distinction matters because the core constraints on housing supply sit elsewhere. Construction costs remain elevated due to materials and labour. There is still a large gap between what new dwellings cost to deliver and what near-new stock built pre-COVID trades at. In many areas, this gap makes new construction commercially unviable.

Bank valuations often fall short of delivery costs. Projects struggle to secure presales. Developers cannot obtain finance. As a result, they do not build.

A CGT change does nothing to resolve those constraints.

Short-term effects: adjustment before equilibrium

If a material CGT change is announced with a future start date, the initial effects are likely to be behavioural rather than structural.

The first response is often a pull-forward of selling. Investors who were already considering an exit may choose to sell before the new rules apply. This can temporarily increase listings and transaction volumes.

Once the change takes effect, the opposite tendency usually emerges. Selling becomes more expensive, so turnover falls. Investors delay selling unless there is a strong reason to exit. Economists describe this as a lock-in effect. In simple terms, fewer discretionary sales occur.

This creates a paradox that much commentary overlooks. Lower turnover can support prices even if demand softens, because fewer properties come to market.

Consider a simple example.

An investor buys a property for $600,000 and later sells it for $1,000,000. Under the current system, half the $400,000 gain is taxed. If the discount is reduced, the tax payable on sale rises materially. That does not make the property less useful, nor does it force a sale. It simply raises the cost of exiting.

Many owners respond by not selling.

During this adjustment period, housing demand does not disappear. Instead, the composition of buyers shifts. If investor participation falls at the margin, first home buyers often fill part of that gap, particularly in more affordable segments where borrowing constraints still allow transactions to clear.

This is why many models show only modest aggregate price effects even when taxes rise. The market does not collapse. It reorganises.

Long-term effects: the mix of return changes, not the existence of return

Over the long run, a lower CGT discount changes the shape of returns.

When selling becomes more expensive, strategies that rely heavily on capital gains become less attractive relative to those that emphasise income and long holding periods. That does not mean property stops working as an asset class. It means the balance between yield and growth shifts.

This is where international comparisons are useful.

The UK as a reference point, not a blueprint

The UK provides a helpful analogue because residential property investment there has long been subject to less generous tax treatment than in Australia.

Historically, capital growth in the UK has been lower than in Australia, while rental yields have been higher. Total returns are broadly comparable, but with a heavier weighting toward income and less reliance on price appreciation.

When disposal costs are higher and tax settings favour income over turnover, investors tend to hold assets longer. Turnover falls. Yield becomes more important. Capital growth still occurs, but compounds more slowly.

For long-term holders, this often results in higher internal rates of return because the asset does more work through income and less through repeated buy-sell cycles that reset tax and transaction costs.

If you never sell, higher disposal taxes are largely irrelevant. If you sell frequently, they matter a great deal.

Effect on supply and rents

Because CGT changes do not address construction feasibility, they do little to improve housing supply in the short term.

If Australia maintains high migration levels, and around three quarters of new arrivals initially enter the rental market, a reduction in investor participation means more households competing for a smaller pool of rental properties. That pressure is reflected in rents.

Prices and rents respond to different forces. Prices are driven by borrowing capacity and expectations. Rents are driven by household formation, migration, income growth, and dwelling availability.

A policy that reduces rental investment while supply remains constrained simply shifts pressure into the rental market.

A useful historical reference is the period from 1985 to 1987, when rental property losses were temporarily quarantined and could not be offset against wage income. While this was not a CGT change, the mechanism was similar. It reduced the attractiveness of being a landlord at the margin.

During that period, rents rose sharply in Sydney and Perth, while other cities were less affected, likely because vacancy rates were already extremely tight in those markets. The lesson is not that any tax change causes rent spikes. It is that when rental markets are already tight, policies that reduce investor participation can be quickly reflected in rents, even though overall housing demand has not changed.

Two possible endings, depending on design

Conclusion A: a cautious change with limited market impact

If the government opts for a cautious design with extensive grandfathering, long lead times, or a modest reduction in the discount, the market impact is likely to be limited.

Behaviour shifts at the margin rather than abruptly. Turnover slows slightly. Income becomes relatively more important than capital gains. Price growth may moderate, but there is little reason to expect large or sudden declines.

For long-term investors, this environment rewards patience, disciplined selection, and assets that stand on their own cash flow. It is not a regime shift. It is a gradual change in emphasis.

Conclusion B: a broader change with clearer behavioural effects

If the change is broader, applying to future sales with limited grandfathering, the adjustment period will be more visible.

There is likely to be a temporary increase in selling ahead of implementation, followed by lower turnover once the new rules apply. Investor participation falls at the margin, particularly among strategies that rely primarily on capital growth rather than income.

At the lower end of the market, first home buyers tend to absorb some of that gap, supporting prices in entry-level segments. Over time, if migration remains high and supply does not respond, rental pressure increases as the pool of rental housing tightens.

The defining feature is not lower returns across the board. Total returns are likely to remain similar, but their composition inverts. Yield becomes dominant, and capital growth slows. This mirrors the UK experience.

Final observation

The mistake in moments like this is treating the housing market as a single, uniform system.

A CGT change, if it occurs, does not rewrite the laws of supply and demand. Total demand and total supply remain largely unchanged. The real effects lie in how demand is distributed during the adjustment period and how incentives around selling and holding evolve.

The ultimate winners and losers are determined less by the headline and more by how well an asset performs when turnover slows and holding periods lengthen. That is where the real-world impact for investors should be assessed.