How Offset Accounts and Redraw Facilities Actually Work
An offset account is a transaction account linked to your home loan. The balance sitting in that account is offset against your outstanding loan principal on a daily basis, and you are charged interest only on the difference. If your loan balance is $600,000 and your offset account holds $50,000, you are effectively paying interest on $550,000. The money in the offset account remains fully accessible at all times — it is yours, sitting in a bank account, and you can withdraw it freely without any approval process. You also continue to earn the full interest benefit on every dollar while it stays there.
A redraw facility works differently. You make extra repayments above your minimum required amount, and those extra repayments reduce your outstanding loan balance directly. The lender then allows you to withdraw, or "redraw," those extra funds at a later date. The mechanical interest-saving effect is similar to an offset account in normal circumstances — you are reducing the balance on which interest accrues — but the funds are no longer sitting in a separate account. They have been applied against the loan. Crucially, the lender controls the redraw process, and some lenders can restrict access, change terms, or in rare cases freeze redraw in financial hardship scenarios.
For owner-occupiers who never intend to convert their home to an investment property and who have no other investment loans, the practical difference between the two features is relatively modest. Both reduce the daily interest charge and both allow access to surplus funds. The choice in that context often comes down to fees, account functionality, and the borrower's ability to maintain discipline — keeping money in a redraw-linked loan prevents the temptation to spend it, which suits some borrowers well.
For anyone with an investment property or a future plan to purchase one, however, the distinction becomes critical, and the redraw route carries a risk that is widely misunderstood.
The ATO's Critical Distinction — and Why It Matters for Investors
The ATO's tax treatment of offset accounts versus redraw facilities diverges sharply when a property changes its purpose, or when borrowed funds are mixed with different uses. The core principle in Australian tax law is that the deductibility of interest depends on the purpose of the borrowing — specifically, whether the borrowed money was used to produce assessable income. An offset account does not change the character of the underlying loan, because the funds in the offset account are simply sitting beside the loan rather than within it. The loan balance and its purpose remain intact.
Redraw creates a different problem. When a borrower redraws funds from an investment loan and uses them for a private purpose — say, a holiday, a car, or renovations on the family home — the ATO views that redraw as a new borrowing. The interest attributable to the redrawn amount then loses its deductibility, because those borrowed funds are no longer used to produce income. Worse, if principal and interest repayments have been blended within the one loan account, it can become extremely difficult to trace which portion of the balance relates to the original investment purpose and which relates to the private redraw. This is what tax professionals refer to as loan contamination, and it can permanently reduce the deductible portion of a loan without any easy remedy.
When investors redraw from an investment loan for private purposes, the ATO treats that redraw as a new borrowing with a new purpose — and interest on that portion immediately loses its deductibility. An offset account, by keeping funds structurally separate, preserves the loan's original character and protects the full deduction.
The practical implication is straightforward: investors should generally hold surplus funds in an offset account rather than making extra repayments into the loan itself. This preserves the loan balance at the highest possible level (maximising the deductible debt) while still delivering an identical interest saving on a day-to-day basis. The offset account is also fully accessible for private spending without touching the loan balance at all. For a deeper understanding of how rentvesting strategies interact with these loan structures, the Rentvesting Explained guide covers the interplay between where you live and where your deductible debt sits.
When Redraw Can Still Make Sense — and for Whom
The offset account is not always the superior product in every situation. Lenders typically charge a higher annual fee, or a slightly higher interest rate, for loans that include a full-featured offset account — particularly 100% offset accounts on fixed-rate loans, which are far less commonly offered than variable-rate offset products. For a borrower on a tight budget, paying a meaningful annual package fee to access an offset account is only worthwhile if the interest saving generated by the offset balance exceeds that fee. A borrower with a very small balance in their offset account — a few thousand dollars — may find the fee outweighs the benefit, and a basic variable loan with redraw could be the more cost-effective choice.
Owner-occupiers who have no current or planned investment property, and who genuinely want to pay down their home loan as fast as possible without drawing funds back out, can also use redraw productively. The behavioural discipline of having extra repayments locked inside the loan — rather than sitting in a transactional offset account where they might be spent — suits many borrowers who have historically struggled to build savings. In that context, the slightly reduced accessibility of redraw funds is a feature rather than a drawback. For borrowers weighing these trade-offs across a full rate cycle, the REAStats property finance data provides useful context on how variable-rate loan structures have performed across recent RBA cycles.
Fixed-rate borrowers face an additional constraint: most lenders do not offer a 100% offset account on fixed-rate loans. Some offer a partial offset, and others offer none at all. Extra repayments on fixed loans are often capped, and break costs apply if the loan is discharged early. In a fixed-rate period, the redraw question may be moot — the structure of the product limits both extra repayments and access to them. This is one reason many investors prefer variable-rate loans for their investment properties, preserving full flexibility on the offset account.
Practical Steps for Australian Borrowers in 2026
With the RBA cash rate at 4.35% following a rate hike cycle, every dollar sitting in an offset account is delivering an interest saving equal to the loan's variable rate — typically well above what a standard savings account pays after tax. This makes the offset account especially powerful in the current environment: the effective return on cash held in an offset is higher than in previous low-rate periods, and there is no income tax payable on the interest saved (because it is a reduction in cost rather than earned income). A borrower in a higher marginal tax bracket benefits disproportionately from this structure compared with holding savings in a taxable account. For a comprehensive breakdown of how these financing mechanics fit within a broader property investment framework, the Australian Property Tax Guide covers the interaction between loan structures, deductibility, and holding costs in detail.
Investors who currently have surplus funds sitting inside their investment loan via extra repayments should discuss with their accountant whether it is advisable to leave those funds in place or restructure. Redrawing from a loan that has already been used for mixed purposes can be complex and should never be done without tax advice. For those setting up a new investment loan, the clean structure is clear: keep the investment loan at its original balance, park surplus cash in an offset account, and avoid making extra repayments into the loan principal unless there is no intent to ever access those funds again.
For owner-occupiers who may one day convert their home to an investment property — a common outcome for borrowers who move into a new home without selling the old one — the offset account structure is essential from day one. Making extra repayments into the owner-occupier loan before it converts to an investment loan permanently reduces the deductible debt, because the ATO assesses deductibility based on the loan balance at the time the property begins producing income, not on the original purchase price. Keeping those funds in an offset account instead preserves the maximum deductible balance for the moment the property becomes an investment — a distinction that can be worth tens of thousands of dollars in deductions over a full investment holding period. Borrowers exploring this transition as part of a broader rentvesting approach will find the strategic framework outlined at APF's First Home Buyer guide a useful starting point for structuring the first purchase correctly from the outset.
This article was produced with AI assistance and reviewed for accuracy. Content is for informational purposes only and does not constitute financial or property investment advice.
