How interest rates impact your loan.
Interest rates play a central role in how much your home loan costs over time. Even small changes can influence your monthly repayments, the total interest you pay, and how quickly you can reduce your loan balance.
Understanding how interest rates work, the difference between fixed and variable options, and how lenders set pricing helps you make confident decisions. At Lumo, we guide clients through choosing the rate structure that best suits their financial goals and risk comfort.
What interest rates actually represent
The interest rate is the percentage your lender charges for providing the loan. It determines the cost of borrowing money and affects your repayment amount each period.
Interest on most home loans is calculated daily and charged monthly.
This means:
The lower your loan balance, the less interest you pay
The more money in offset or extra repayments, the more interest saved
Even a small rate adjustment can result in significant savings over the life of a loan.
Variable interest rates
Variable rates move in line with market conditions, including economic trends and the lender’s cost of funding. Lenders can change variable rates at any time.
Advantages of variable rates
Flexibility to make unlimited extra repayments
Often includes features like offset and redraw
You benefit when rates decrease
Freedom to refinance without break costs
Considerations
Repayments can rise if rates increase
Less certainty for long-term budgeting
Variable rates suit borrowers who want flexibility and can adjust comfortably if rates move.
Fixed interest rates
Fixed rates lock in your interest rate for a set term (usually 1–5 years). During this time, your repayments stay the same regardless of market changes.
Advantages of fixed rates
Certainty of repayments
Useful for budgeting and planning
Protection from rising rates
Considerations
Limited ability to make extra repayments
Offset accounts may not be available or may be partial
Break fees may apply if you refinance or change the loan during the fixed term
You may miss out on savings if rates drop
Fixed rates work well for borrowers who value stability and predictability.
Split loans: a balanced approach
A split loan combines both fixed and variable components.
For example:
60% fixed for stability
40% variable for flexibility
Why splits can be useful
Provides certainty over part of the loan
Maintains access to offset or redraw on the variable portion
Reduces risk in a shifting rate environment
At Lumo, we see many clients choose splits when navigating periods of economic uncertainty.
How lenders set interest rates
Lenders consider several factors when pricing your loan:
Funding costs
Economic forecasts
Competitor rates
Loan-to-value ratio (LVR)
Loan purpose (owner-occupied vs investment)
Repayment type (principal & interest vs interest-only)
Borrower profile
Market competition
This is why two borrowers with similar incomes may still receive different pricing depending on their scenario.
How interest rate changes affect your repayments
Rate changes can impact your loan significantly:
When rates rise
Repayments increase
More of your payment goes towards interest instead of principal
Long-term interest cost increases
When rates fall
Repayments decrease
More of your payment reduces the principal
Opportunities arise to pay the loan off faster
We help clients understand these shifts and adjust strategies as the market evolves.
Staying ahead in a changing rate environment
You can stay in control by:
Reviewing your loan annually
Using offset accounts effectively
Making extra repayments when possible
Considering split structures
Refinancing if better options become available
A proactive approach can save substantial interest over the life of the loan.
Let’s chat.
Want help choosing between fixed, variable or split rates — or understanding how a rate change would impact your loan? At Lumo, we help you make confident, informed decisions. Let’s chat.
This page provides general information only and has been prepared without taking into account your objectives, financial situation or needs. We recommend that you consider whether it is appropriate for your circumstances and your full financial situation will need to be reviewed prior to acceptance of any offer or product. It does not constitute legal, tax or financial advice and you should always seek professional advice in relation to your individual circumstances. Subject to lenders terms and conditions, fees and charges and eligibility criteria apply.