If you own an investment property on the Mornington Peninsula and have been quietly thinking about selling, the federal budget delivered on 12 May 2026 just put a clock on the conversation.
From 1 July 2027, the long-standing 50% capital gains tax discount on investment property will be replaced by inflation indexation combined with a 30% minimum tax rate on the gain. That gives Peninsula vendors a clearly defined fourteen-month window, including the current 2025-26 financial year ending next week to settle a sale under the existing regime.
This isn’t a prompt to rush a decision. It’s a prompt to start the conversation with your accountant now, while the timeline still allows for a properly run campaign rather than a fire sale.
What’s actually changing
The 50% CGT discount has been a fixture of Australian property investment since 1999. Anyone holding an asset for longer than twelve months has been entitled to halve their assessable capital gain when calculating tax. For Peninsula investment properties held since the early 2000s, that discount has often been worth hundreds of thousands of dollars at sale.
From 1 July 2027, the system changes in two ways. First, the flat 50% discount is replaced by cost base indexation — your purchase price is adjusted upward for inflation between the year of acquisition and the year of sale, which reduces the calculated gain. Second, a new 30% minimum effective tax rate applies to whatever capital gain remains after indexation.
For investors who bought in long-inflation periods, indexation can produce a result reasonably close to the old discount. For those who acquired in lower-inflation years or held shorter periods, the new regime is meaningfully less generous.
Importantly, the changes apply only to gains arising after 1 July 2027. Any sale where settlement occurs before that date is calculated under the existing 50% discount rules. The contract date matters less than the settlement date for CGT timing purposes.
Why this matters more on the Peninsula
A meaningful share of Peninsula investment property has been held for decades. Coastal holdings in Sorrento, Portsea, Blairgowrie and Rye acquired in the 1990s and 2000s have appreciated significantly. Established investment stock in Mornington, Mount Eliza, Mount Martha and Safety Beach has tracked similar long-term growth curves.
Consider a hypothetical. An investor purchased a Mount Martha investment property in 2008 for $620,000. It’s now worth $1.4 million. Under the existing 50% discount regime, the assessable gain after deducting acquisition and disposal costs is approximately halved before tax is applied. Under the post-2027 rules, indexation will adjust the cost base upward — but the floor of a 30% effective rate on the indexed gain produces a different outcome.
The actual tax difference between selling pre-July 2027 versus post-July 2027 will vary substantially depending on holding period, original purchase price, marginal tax rate, and the inflation trajectory over the holding period. None of those calculations should be done on the back of an envelope. They should be modelled by your accountant using your actual figures.
What this discussion gives you is awareness that 2025-26 and 2026-27 sit inside a defined window and that the planning conversation worth having is the one that happens now rather than in early 2027 when the runway to a properly marketed sale has narrowed.
Three scenarios for Peninsula vendors
If you’ve been considering selling within the next two years anyway, the budget changes have effectively brought your timeline forward. A sale settled before 1 July 2027 retains existing treatment. A spring 2026 launch settling late 2026 or early 2027 sits comfortably inside the window. An autumn 2027 launch is the practical outer edge you’d need settlement before 1 July to retain the old regime.
If you’re holding a Peninsula property that you intended to hold for another five to ten years, the calculus is more complex. The CGT change reduces your future after-tax return but doesn’t eliminate it. Combined with the negative gearing changes announced in the same budget, which restrict deductions for established residential property bought after 12 May 2026. The overall economics of long-term established property holdings have shifted. Whether that justifies bringing a sale forward depends entirely on your situation and is exactly the conversation to have with your accountant.
If you weren’t considering a sale at all, nothing about the budget changes that. The 50% discount disappearing doesn’t make holding a bad decision. It just makes the after-tax return on eventual sale lower than it would have been.
What doesn’t change
The main residence exemption is unaffected. Property used as your principal place of residence remains exempt from capital gains tax on sale, regardless of when it’s sold.
Properties held inside self-managed super funds are unaffected by the CGT discount changes and SMSFs were explicitly excluded from the budget reforms and retain the existing concessional treatment (an effective 10% rate on assets held over 12 months in accumulation phase, and 0% in pension phase).
The CGT six-year rule for former main residences also remains in place. Properties that were once your home and have been rented for less than six years can still be sold CGT-free in certain circumstances, subject to the standard eligibility requirements.
Why getting it right matters
If you do decide to sell within the window, the runway matters. A properly run Peninsula sales campaign and pre-marketing, photography in good light, professional copy, an authentic four to six week marketing period, then auction or expressions of interest and typically takes eight to twelve weeks from listing decision to settlement. Add 30 to 60 day settlement terms after exchange and you’re looking at a four to five month timeline from go-decision to settlement under normal conditions.
That means a vendor wanting to settle before 1 July 2027 has comfortable runway right now. A vendor making the same decision in late 2026 has tighter runway. A vendor making the decision in early 2027 has very little runway and risks either a rushed campaign or missing the deadline.
The point of this post isn’t to push anyone toward a decision. It’s to flag that the decision window is defined and that conversations with accountants are best had now, not in twelve months.
What to do next
If any of this applies to you, the right starting point is a conversation with your accountant, They can model the actual tax difference between a sale inside the window versus outside it, using your specific cost base, holding period, and marginal rate.
Once you have that picture, the property-side conversation is one we’re happy to have. Current Peninsula market values, realistic timing across the suburbs you may hold in, and how the broader market is positioned through the back half of 2026 are all things we can help with. Whether or not it’s the right moment to sell is a decision that belongs with you and your advisers — but the data and the market read are something we can usefully contribute.
Disclaimer
This article is general information only and does not constitute financial, legal or taxation advice. The legislation referenced is current as at June 2026 and remains subject to further amendment. Speak to a registered tax agent, accountant or financial adviser before making any decision based on the matters discussed.
