Do you know how to optimise your investment loan?

Loan Structure Drives Returns, Not Just Rate

Your loan structure affects your cash flow, tax position, and ability to grow your portfolio more than the interest rate alone. Choosing between interest-only and principal-and-interest repayments, splitting your loan, or setting up an offset correctly can shift your tax outcome and free up cash for your next purchase.

Consider an investor in South Perth who bought a two-bedroom apartment near the foreshore. The property was generating rental income, but the investor was paying principal and interest on the loan while holding cash in a non-offset savings account. Switching to interest-only repayments and moving that cash into an offset against their owner-occupied loan reduced non-deductible interest on their home while maximising the tax-deductible debt on the investment. Over three years, the change saved around $7,000 in after-tax interest and preserved borrowing capacity for a second property.

Interest-only periods typically run for one to five years and can be renewed depending on your lender and loan-to-value ratio. The repayments are lower because you're not reducing the loan balance, which keeps more cash available each month. That cash can be redirected toward another deposit, offset against non-deductible debt, or held as a buffer for vacancies and repairs. When the interest-only period ends, the loan reverts to principal and interest unless you request an extension or refinance.

Offset Accounts and Redraw: Why the Distinction Matters

An offset account linked to your investment loan reduces the interest you pay, but it doesn't reduce your tax deduction. A redraw facility lets you access extra repayments you've made, but those repayments reduce your loan balance and your claimable interest.

If you're making extra repayments on an investment loan and then redrawing for personal expenses, the ATO may question whether the redrawn amount is still used for income-producing purposes. That can reduce or eliminate the deduction on the redrawn portion. An offset avoids this problem because your loan balance stays constant and the full interest amount remains deductible. For investors juggling multiple properties or planning to use equity for future purchases, keeping deductible and non-deductible debt separate is essential.

Recent Budget Changes and What They Mean for Established Properties

From 1 July 2027, negative gearing and capital gains tax treatment will change for established residential properties bought after 12 May 2026. If you bought before that date, your existing arrangements continue. If you're buying now, rental losses on established properties will only be deductible against other residential property income, not against wages. The 50% capital gains discount will be replaced with indexation and a minimum 30% tax on gains.

New builds remain exempt from both changes, and investors buying new construction can still claim the 50% CGT discount or choose the indexed rate, whichever is more favourable. Commercial property and other asset classes are unaffected. If you're considering an established property in South Perth and plan to settle after Budget night, factor in the reduced scope for offsetting losses and speak to your accountant about structuring the purchase to suit the new rules.

Loan Splitting for Flexibility and Rate Protection

Splitting your investment loan between variable and fixed portions lets you lock in part of your rate while keeping access to offset benefits and extra repayments on the variable portion. A common split is 50/50 or 60/40 variable to fixed, but the right mix depends on your cash flow, rate outlook, and whether you plan to sell or refinance.

Fixed rates don't allow offset accounts or unlimited extra repayments, and early exit can trigger break costs. Variable rates give you full flexibility but expose you to rate rises. Splitting the loan gives you partial protection without locking the entire balance. If rates fall, your variable portion benefits immediately. If they rise, your fixed portion shields part of your repayment. You can also stagger fixed terms so they expire at different times, which smooths the transition when rates reset.

Using Equity Without Selling

As your property increases in value or your loan balance falls, you build equity that can be accessed to fund another deposit without selling. Lenders typically allow you to borrow up to 80% of your property's value without paying Lenders Mortgage Insurance, though some will lend higher if you're willing to cover the premium.

Consider an investor who bought in South Perth several years ago. The property's value increased, and the loan balance dropped, leaving enough equity to borrow an additional amount for a deposit on a second property. Rather than saving from income alone, the investor used that equity and kept both properties. The rental income from the first property supported part of the second loan, and both loans remained interest-only to maximise deductible interest and preserve cash flow.

When you access equity, the new borrowing is added to your existing loan or set up as a separate split. Keeping the new funds in a separate split makes it simpler to track how the money was used, which matters for tax purposes. If the funds are used to buy another investment property, the interest on that split is deductible. If they're used for personal expenses, it's not. Mixing the two in one loan account creates confusion and can lead to lost deductions.

Why Loan Features Should Match Your Strategy

Not every investor needs the same loan. If you're holding long-term and reinvesting cash flow into other properties, an interest-only loan with offset and portability makes sense. If you're planning to pay down debt before retirement, principal-and-interest with redraw might suit you now, but you'll want the option to switch back to interest-only if your strategy changes.

Portability lets you move your loan to a new property without refinancing, which can save time and costs if you sell and buy in quick succession. Some lenders also offer rate discounts for larger loan balances or multiple properties, though the discount only matters if the base rate and features align with your needs. Before locking in a loan based on rate alone, check the flexibility, fees, and whether the lender will extend interest-only periods or allow top-ups without a full reapplication.

Rental Income, Vacancy Buffers, and Serviceability

Lenders assess your ability to repay based on your income, existing debts, and the rental income the property generates. Most lenders only count 80% of the rental income to account for vacancies, and they apply a higher interest rate buffer when calculating serviceability. That means you need to show you can afford the repayments even if rates rise or the property sits vacant for a period.

South Perth has a relatively low vacancy rate due to its proximity to the city and the foreshore, but short-term vacancies still happen during lease transitions or maintenance periods. Holding a buffer in an offset account or redraw gives you coverage without needing to dip into personal savings. For tax purposes, expenses like body corporate fees, property management, insurance, and loan interest are all claimable, which reduces your taxable income and improves cash flow after tax.

When Refinancing Makes Sense

If your loan no longer suits your strategy, or if your lender won't extend your interest-only period or offer the rate discount you're entitled to, refinancing can reset your structure and save you money. Refinancing also lets you consolidate debt, access equity, or move to a lender with lower fees or more flexible features.

Before refinancing, check for exit fees on your current loan, compare the cost of switching against the benefit, and confirm the new lender will offer the loan amount and structure you need. A loan health check can identify whether your current loan is still competitive or if you'd benefit from a change. If you've paid down a significant portion of your loan or your property has increased in value, refinancing might also remove Lenders Mortgage Insurance or improve your rate.

Building Wealth Through Property Requires the Right Loan Setup

Property investment works when your loan structure supports your goals, not when it locks you into repayments or terms that limit your options. Whether you're holding one property or building a portfolio, the way you structure your borrowing affects your tax position, cash flow, and ability to reinvest.

If you're investing in South Perth or expanding your portfolio across Perth, call one of our team or book an appointment at a time that works for you. We'll review your current setup, discuss your strategy, and help you access investment loan options that align with where you're headed.

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