Investment Loans: Fixed Rates and Offset Accounts Explained

Investment Loans with Fixed Rates: What Changes

A fixed rate on an investment loan locks in your interest cost for a set period, typically between one and five years. The rate remains unchanged regardless of market movements, which provides certainty for budgeting your cash flow and calculating your tax position each year.

Most lenders apply higher risk weights to investor loans compared to owner-occupied borrowing under prudential standards, which translates to a pricing margin. In our experience, fixed rates for investors sit roughly 0.10 to 0.30 percentage points above equivalent owner-occupier fixed products, though this varies by lender and loan size.

Consider a buyer who acquires a two-bedroom apartment near Northcote's High Street precinct as a rental property. They fix the rate at 5.89 per cent for three years on a loan amount of $550,000. For the duration of that fixed period, the interest cost is $32,395 per year, which remains deductible regardless of whether rental income covers it. The investor knows exactly what their holding cost will be and can plan around that figure when assessing whether the property fits their tax and cash flow position.

Do Offset Accounts Work with Fixed Rate Investment Loans?

Offset accounts are generally not available on fixed rate investment loans. Lenders structure fixed rate products to hedge their own funding costs, and allowing an offset account introduces variability that conflicts with that hedge. A small number of lenders offer partial offset functionality on fixed investor loans, but the feature is typically limited to a maximum offset balance or attracts a higher fixed rate.

Even where an offset is available on a fixed investment loan, the tax treatment makes it less valuable than on an owner-occupied loan. Interest saved through an offset reduces the amount of deductible interest you pay, which means you lose the tax benefit on that portion. For an investor in the 37 per cent marginal tax bracket, every dollar of interest saved in an offset reduces deductible expenses by the same amount, effectively reducing the after-tax benefit of the offset to around 63 cents.

Most investors who want rate certainty choose a fixed rate loan without offset and manage surplus cash in other ways. Strategies include paying down non-deductible debt such as an owner-occupied mortgage, directing surplus funds into redraw facilities on variable rate portions of an investment loan, or holding cash in separate accounts to meet future capital expenses on the property without triggering a mixed-purpose loan.

The Split Loan Structure: Combining Fixed and Variable Rates

A split loan structure divides your total borrowing into two or more portions, each with different terms. One portion may be fixed for certainty, while the other remains variable with an offset account attached. This structure is common among property investors who want some protection against rate rises without giving up all flexibility.

In a scenario like this, an investor borrows $600,000 to purchase a townhouse in South Yarra. They fix $400,000 at 5.79 per cent for four years and leave $200,000 on a variable rate at 6.15 per cent with a linked offset account. Rental income and any surplus cash flow sit in the offset, reducing interest on the variable portion. The fixed portion provides a floor for budgeting, while the offset portion allows the investor to manage cash and reduce interest costs where it remains tax effective.

The split can be adjusted when the fixed term expires. Some investors increase the variable portion over time as their cash reserves grow, while others re-fix a smaller portion if they expect rates to rise further. The structure works well where the investor's income is variable or where they plan to access equity from the property within a few years, as the variable portion can be redrawn or refinanced without incurring break costs.

For more detail on how refinancing works when moving between fixed and variable structures, or if you are approaching the end of a fixed term, refer to the fixed rate expiry section of our site.

Fixed Rate Break Costs: How the Calculation Works

Break costs apply when you exit a fixed rate investment loan before the fixed term ends. The cost reflects the difference between the rate you locked in and the rate the lender can now achieve by re-lending that money for the remaining fixed period. If rates have fallen since you fixed, the break cost can be substantial. If rates have risen, the break cost may be zero or even result in a rebate.

The calculation uses the economic cost method, which compares the present value of the remaining fixed payments to the present value of what the lender would receive by reinvesting at current wholesale rates. Break costs are not uniform across lenders, as each institution uses slightly different discount rates and funding curves. A break cost on a three-year fixed loan with two years remaining might be $15,000 at one lender and $18,000 at another for the same loan amount and rate, depending on their treasury model.

Break costs are generally not tax deductible as a standalone expense when you sell an investment property, but they may be deductible over five years if you refinance the same investment loan to another lender and continue to use the funds for income-producing purposes. Seek advice from a registered tax agent on the treatment in your specific circumstances.

Interest-Only Fixed Loans for Property Investors

Interest-only loans allow you to pay only the interest component of the loan for a set period, typically up to five years, without reducing the principal. This structure is common for investment loans because it maximises deductible interest, keeps repayments lower, and frees up cash flow for other investments or to offset against non-deductible debt.

You can combine interest-only repayments with a fixed rate. The interest-only period and the fixed rate term do not need to align. An investor might choose a five-year interest-only period with a two-year fixed rate, after which the loan reverts to a variable rate but remains interest-only for the remaining three years. Alternatively, a three-year interest-only period might sit within a five-year fixed term, after which the loan converts to principal and interest repayments while still fixed.

Lenders apply higher risk weights under APS 112 to interest-only investment loans, particularly where the loan-to-value ratio exceeds 80 per cent or the interest-only term exceeds five years. This typically results in a higher interest rate compared to a principal and interest investment loan at the same LVR. The rate loading varies by lender but is often between 0.15 and 0.40 percentage points.

When the interest-only period ends, your loan converts to principal and interest repayments. The remaining term is used to amortise the loan, which increases the repayment amount significantly. For a $500,000 loan at 6.00 per cent, the interest-only repayment is $2,500 per month. After five years, if the loan converts to principal and interest over the remaining 25 years, the repayment rises to approximately $3,220 per month. Investors need to plan for this increase or arrange to extend the interest-only period before it expires, which usually requires a formal application and updated serviceability assessment.

How Lenders Assess Investment Loan Serviceability with Fixed Rates

Lenders assess your ability to service an investment loan by applying a minimum interest rate buffer of 3.0 percentage points above the loan product rate, regardless of whether you choose a fixed or variable rate. If you apply for a fixed rate of 5.89 per cent, the lender tests your ability to service the loan at 8.89 per cent. This buffer has been in place since October 2021 and applies to all new borrowing from authorised deposit-taking institutions.

Rental income is included in the serviceability calculation, but lenders typically apply a shading factor of 20 per cent to account for vacancy and maintenance costs. If the property generates $2,400 per month in rent, the lender will assess serviceability using $1,920 per month. Some lenders apply higher shading in areas with higher vacancy rates or for property types such as studio apartments.

Debt-to-income limits also apply from February 2026. Lenders can provide no more than 20 per cent of new investor loans to borrowers with a total debt-to-income ratio of six times or greater. If your total borrowings, including the new investment loan, exceed six times your gross annual income, you may be subject to additional assessment or declined depending on the lender's quarterly position against the limit. The DTI calculation includes all debt, not just investment debt, and is measured at the time of application.

For more information on how your total borrowing capacity is calculated across multiple loan types, including investment and owner-occupied debt, refer to the borrowing capacity section of our site.

Variable Rates with Offset: The Alternative for Active Investors

Investors who prefer liquidity and flexibility over rate certainty often choose a variable rate loan with a full offset account. The offset account operates as a transaction account linked to the loan. Every dollar in the offset reduces the balance on which interest is calculated, without reducing the loan balance itself.

The tax treatment differs from a fixed loan. Interest saved through an offset account reduces your deductible interest expense, which means the after-tax benefit is lower than the headline saving. For an investor paying 6.20 per cent variable on a $500,000 loan, holding $50,000 in offset saves $3,100 in interest per year. However, that saving reduces deductible interest by the same amount, which for an investor in the 37 per cent tax bracket means the after-tax cost of the saving is approximately $1,953. The investor is still ahead, but the benefit is less than it would be for an owner-occupier in the same position.

Variable rate investment loans with offset are suited to investors who receive irregular income, plan to make lump sum repayments, or expect to access equity within a few years. The variable rate allows you to increase repayments or pay down the loan without restriction, and the offset provides a buffer for holding cash without losing access to it. If you are considering an investment loan structure that combines multiple rate types, a variable portion with offset is usually the most flexible component.

When Fixed Rates Make Sense for Property Investors

Fixed rates suit investors who value certainty in their tax planning and cash flow forecasting. If you are negatively geared and rely on the tax deduction to manage your overall tax position, knowing the exact interest cost for the next few years removes one variable from your annual return.

Fixed rates also make sense where you expect rates to rise and want to lock in current pricing before that occurs. The risk is that rates fall or remain flat, in which case you pay more than you would have on a variable loan and may face break costs if your circumstances change. Investors who plan to hold the property long-term, do not expect to require additional borrowing against the property during the fixed term, and have stable income are typically well placed to benefit from fixing.

Fixed rates are less appropriate where you expect to sell the property, refinance to access equity, or significantly increase your repayment rate within the fixed period. Each of those events can trigger break costs or limit your flexibility. If you are acquiring a property in an area with strong capital growth, such as Port Melbourne or Hawthorn East, and you expect to leverage equity within two to three years to acquire another property, a variable rate or a small fixed portion within a split loan may be a more practical structure.

Refinancing Investment Loans: Moving Between Fixed and Variable

Refinancing an investment loan from one lender to another while still within a fixed term will trigger break costs. These costs are payable to the existing lender and are separate from any application or settlement fees charged by the new lender. In a falling rate environment, break costs can exceed $20,000 on a large loan with several years remaining on the fixed term.

Investors refinance for several reasons: to access equity for further investment, to secure a lower rate, to consolidate debt, or to move to a lender with more suitable loan features such as higher LVR lending or longer interest-only terms. Where the existing loan is fixed, the decision to refinance requires a comparison between the benefit of the new loan and the cost of exiting the old one, including break costs, application fees, valuation fees, and any new LMI if the LVR increases.

Refinancing is more common at the end of a fixed term, when the loan reverts to a variable rate. At that point, no break costs apply, and the investor can move to a new lender or negotiate a new rate with the existing lender without penalty. Many investors use the fixed rate expiry as a trigger to review their overall loan structure, assess whether their offset and redraw features are being used effectively, and consider whether a different split between fixed and variable suits their current position.

Call one of our team or book an appointment at a time that works for you to discuss your current investment loan structure and whether a fixed rate, variable rate, or split loan approach aligns with your tax position and portfolio goals.

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