Fixed Rate Home Loans: What Not to Lock In Too Long

Fixed Rate Terms Protect You From Rate Rises, Not From Life Changes

A fixed interest rate home loan locks in your repayment amount for a set period, typically between one and five years. That certainty is appealing, especially when variable rates are climbing. But the protection comes with restrictions. If your income jumps, your family grows, or you need to sell before the fixed term ends, you might face break costs that wipe out any savings you made.

Consider a buyer in South Melbourne who locks in a three-year fixed rate at 5.8% on a $650,000 loan. Eighteen months later, they accept a promotion in Sydney and need to sell. The lender calculates break costs based on the difference between the fixed rate they're locked into and the current wholesale rate the lender can reinvest at. If rates have dropped to 5.2%, the borrower might owe $8,000 to $12,000 in break costs, depending on the lender's calculation method and the remaining fixed term. The longer the remaining fixed period, the higher the potential penalty.

This is why the term length matters more than the rate itself. A one-year fixed term offers flexibility with some short-term certainty. A five-year term offers maximum protection from rate rises but maximum exposure to break costs if anything changes. Most borrowers in South Melbourne are balancing job mobility, property upgrades, and family planning over a three-to-five-year horizon, which makes mid-length fixed terms risky unless you're certain your circumstances won't shift.

How Fixed Rate Break Costs Are Calculated

Break costs are calculated using the economic cost method. The lender works out the present value of the interest they'll lose by letting you out of the fixed rate early, minus the interest they can earn by reinvesting your repayments at current wholesale rates. The formula takes into account the remaining fixed term, the difference between your fixed rate and the current wholesale rate, and your outstanding loan balance.

If wholesale rates have risen since you fixed, there may be no break cost at all, because the lender can reinvest at a higher rate than you were paying. If wholesale rates have fallen, you'll owe the difference. The longer the remaining term, the larger that difference compounds. A borrower with four years left on a five-year fixed term will typically face a much higher break cost than someone with one year remaining, even if the rate gap is identical.

Lenders are required to provide an estimate of break costs if you request it, but the final figure is calculated on the day you discharge the loan. That means the estimate you receive in March could be different from the actual cost in June. If you're considering refinancing or selling during a fixed term, request an updated estimate as close to settlement as possible.

Split Loans Let You Test Both Structures Without Overcommitting

A split loan divides your borrowing between fixed and variable portions. You might fix 50% of a $700,000 loan for two years and leave the other 50% on a variable rate. The fixed portion protects half your repayments from rate rises, while the variable portion lets you make extra repayments, redraw funds, or pay down the loan faster without triggering break costs.

This structure works well in South Melbourne, where buyers often purchase apartments or townhouses with the intention of upgrading to a larger home within three to five years. If you fix the full amount for five years and need to sell in year three, you'll face break costs on the entire balance. If you split 50/50 and fix for three years, you'll only face break costs on half the loan, and you'll have been making extra repayments on the variable half to reduce the total balance.

The offset account typically only links to the variable portion of a split loan, so any savings you park in the offset will only reduce interest on that portion. If you're expecting a bonus, inheritance, or sale proceeds from another property, keeping a larger variable portion gives you more flexibility to use those funds effectively. In our experience, borrowers who expect lump sum payments within the fixed term are usually better off with a 30/70 or 40/60 split in favour of the variable portion, rather than a 50/50 split.

Should You Fix Again When Your Current Term Ends?

When your fixed term ends, your loan automatically reverts to the lender's standard variable rate unless you take action. That revert rate is often higher than the variable rate offered to new customers, sometimes by 0.3% to 0.6%. If you're happy with your current lender, you can negotiate a new fixed or variable rate before the fixed term expires. If you've built equity or your financial position has strengthened, you might also qualify for a lower rate by refinancing to a different lender.

If variable rates have fallen significantly since you first fixed, rolling onto a competitive variable rate might give you more flexibility than fixing again. If rates have risen or are expected to rise, locking in a new fixed term could make sense. The decision depends on your circumstances, not just the rate environment.

Many South Melbourne buyers fix their first home loan at purchase and then reassess when the term ends. By that point, they've built equity, their income may have increased, and they have a clearer sense of whether they'll stay in the property or upgrade. Fixing again might make sense if you're planning to stay for another three to five years. If you're likely to sell or renovate, a variable rate or shorter fixed term gives you more room to move.

Fixed Terms and Offset Accounts Don't Work Together

Most fixed rate home loans do not allow you to link an offset account. Some lenders offer a partial offset on fixed loans, but the offset percentage is usually capped at 40% to 60% of the balance, or the feature is only available on certain fixed products with a higher interest rate. If you're fixing the full loan amount, you'll lose the ability to park savings in an offset and reduce your interest in real time.

This is one of the reasons split loans are common. You fix a portion for rate certainty and keep a portion variable with a full offset attached. If you're a South Melbourne buyer with a high savings rate or irregular income, losing offset access on a fully fixed loan could cost you more in foregone interest savings than you gain from fixing the rate.

Before locking in a fixed term, calculate how much you're likely to hold in savings over the fixed period and how much interest that would save you in an offset account. If the answer is more than the rate differential between fixed and variable, you're better off staying variable or splitting the loan.

One, Three, or Five Years: Matching the Term to Your Timeline

One-year fixed terms suit borrowers who want short-term certainty without locking themselves in. The rate is usually lower than longer fixed terms, and the risk of needing to break the loan within 12 months is manageable for most people. If you're buying in South Melbourne and planning to reassess your loan structure within a year, a one-year fix lets you lock in a rate without overcommitting.

Three-year fixed terms are the most common. They balance rate protection with flexibility, and most borrowers can predict their circumstances over a three-year window with reasonable accuracy. If you're planning to stay in your current property, your job is secure, and you don't expect major life changes, a three-year fix gives you certainty without excessive break cost risk.

Five-year fixed terms offer maximum protection from rate rises but carry the highest risk if your circumstances change. They suit borrowers who are certain they'll stay in the property for the full term and don't expect to make lump sum repayments or sell. In practice, few South Melbourne buyers have that level of certainty, which is why five-year fixed terms are less common than shorter options.

If you're weighing up a fixed term or trying to work out the right split, call one of our team or book an appointment at a time that works for you. We'll walk through your timeline, your savings, and what you're likely to face if rates move or your plans change.

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