Fixed Vs Variable Rate Investment Loans

01Two different trade-offs, not two different destinations

Fixed and variable rate loans get you to the same place, a loan secured against your investment property, but they get you there with different trade-offs around certainty, flexibility, and cost if your plans change. Neither structure is inherently better; which one suits a given investor depends on their cash flow needs, how firm their holding period is, and how much they value knowing exactly what a repayment will be each month.

This article compares the mechanics of each structure generally. It doesn't state or predict specific interest rates, since current rates move over time and differ by lender, loan product, and borrower profile — for an actual rate, you'd compare current offers from lenders or a mortgage broker.

02Variable rate loans

With a variable rate loan, the interest rate moves in line with changes the lender makes to its variable rate, which is influenced by, but not identical to, movements in the broader interest rate environment. Your repayments rise or fall as the rate changes over the life of the loan.

Flexibility is the main advantage. Variable loans typically allow unlimited extra repayments without penalty, offer access to features like offset accounts and redraw facilities (see offset account vs redraw facility for how those work), and generally don't carry break costs if you refinance, sell, or pay the loan off early.

Uncertainty is the corresponding downside. Because the rate can move, your repayment amount isn't fixed, which can make cash flow planning harder, particularly if you're running a portfolio close to the edge of serviceability or relying on tight rental yields to cover repayments.

03Fixed rate loans

With a fixed rate loan, the interest rate is locked for an agreed period (commonly a few years, though terms vary by lender), after which the loan typically reverts to a variable rate or you can choose to fix again.

Certainty is the main advantage. Your repayment amount is known for the fixed term, which can make budgeting and cash flow forecasting more straightforward, particularly useful if you're running a portfolio where rental income is closely matched to loan repayments.

Reduced flexibility, and break-cost risk, are the main downsides. Fixed loans commonly limit or restrict extra repayments during the fixed period, often capping additional payments at a set amount before extra fees apply. More significantly, if you want to exit the fixed loan early, whether by refinancing to a better deal, selling the property, or restructuring your finances, the lender can charge a break cost.

04Understanding break costs

Break costs exist because when a lender fixes your rate, it typically arranges its own funding at a matching fixed cost for that period. If you exit early, the lender may have a cost to unwind that funding arrangement, and this cost is passed on to you as a break fee.

Break costs are generally calculated with reference to the difference between the rate you fixed at and the rate the lender could now fix at for the remaining term, applied against your outstanding loan balance and the time remaining on the fixed period. In practice, this means:

• Break costs tend to be larger the more time is left on the fixed term.
• Break costs tend to be larger the more the relevant wholesale rate environment has moved since you fixed.
• Break costs can, in some interest rate environments, be substantial, sometimes running into thousands of dollars.
• Break costs apply on top of any other exit fees or discharge fees the lender may separately charge.

This is a genuine and sometimes underestimated risk for property investors specifically, because investment strategies often involve selling a property, refinancing to access equity, or restructuring a loan structure sooner than an owner-occupier might. Fixing a loan for a long term on a property you might sell in a shorter timeframe is one of the more common ways investors end up facing an unexpected break cost. Because break costs are calculated differently by each lender and depend on market conditions at the time you exit, this article doesn't attempt to quantify them, exact figures require a calculation from your specific lender at the time.

05Split loans as a middle option

A split loan divides your loan balance into a fixed portion and a variable portion, each governed by its own rate and terms. This structure is designed to capture some of the benefit of each approach:

• The fixed portion provides repayment certainty on part of your debt.
• The variable portion retains flexibility, including the ability to make extra repayments, use an offset account, or refinance that portion without a break cost.
• If you need to exit early, only the fixed portion is exposed to break-cost risk, which can meaningfully reduce the total break cost compared with fixing the entire loan.

The proportion you choose to fix versus keep variable is a judgment call based on how much certainty you want, how confident you are in your holding period, and your broader cash flow position. There's no universally "correct" split, it's a genuine trade-off decision worth discussing with a mortgage broker who can model different scenarios against your specific loan and plans.

06Weighing the decision for an investment loan

For an investment property specifically, a few extra considerations are worth thinking through alongside the general fixed-versus-variable trade-off:

• How firm is your intended holding period? A shorter or uncertain holding period increases the relative risk of break costs on a fixed loan.
• Do you rely on extra repayments or an offset account as part of your cash flow strategy? These features are typically more available, or fully available, on variable loans.
• How tight is your serviceability margin? If a rate rise would put real pressure on your cash flow, the certainty of a fixed rate may be worth more to you than the flexibility of a variable one.
• Are you likely to refinance to access equity for a future purchase? Frequent refinancing activity sits more comfortably with a variable or split structure.

Use the mortgage repayment calculator to model how repayments compare under different rate and term assumptions, and see LVR and lending for investors in Australia for how loan structure decisions interact with your overall lending position.

This article is general educational content, not personal financial advice. It does not state or predict specific interest rates, which change over time and vary by lender and borrower. Speak with a mortgage broker or lender for current rates and a break-cost estimate specific to your loan.