Lenders don’t just look at your income when deciding how much you can borrow. They assess your overall financial situation to see what you can comfortably repay, even if interest rates rise. This means your borrowing power is shaped by several things working together, not a single number.
What Really Drives Your Borrowing Capacity
Your borrowing capacity is built from a mix of your financial picture and industry-wide rules. Here are the main pieces:
- Income: Lenders consider your stable, ongoing income—salary, wages, and sometimes rental income or other reliable sources. Casual or irregular income may be discounted.
- Expenses: This includes day-to-day living costs, which many lenders benchmark against the Household Expenditure Measure (HEM), plus any declared discretionary spending.
- Existing debts: Credit cards, personal loans, car finance, and HECS-HELP commitments all reduce the amount a lender thinks you can afford.
- Credit history: A strong credit score and clean repayment history help. Defaults or late payments can limit your options and borrowing amount.
- Deposit size: A larger deposit lowers the loan amount and the risk for the lender, potentially improving your borrowing position.
The Serviceability Buffer: Why It Matters
Australian lenders must apply a serviceability buffer when they calculate your repayments. This is set by the Australian Prudential Regulation Authority (APRA) and means your ability to repay is assessed at an interest rate higher than what you’ll actually pay—usually 3 percentage points above the loan’s advertised rate. The idea is to make sure you can still manage if rates go up.
For example, if you apply for a loan with a 6% interest rate, the lender tests whether you could afford repayments at 9%. This buffer can significantly reduce the amount you can borrow, even if your day-to-day budget looks fine at the current rate.
How Lenders Compare You to the Average
While your specific circumstances drive the outcome, comparing loan types and features can also affect your overall affordability. As the Moneysmart guide to choosing a home loan points out, the interest rate, loan term, and whether you choose principal-and-interest or interest-only repayments all influence total costs. A 0.5% difference on a large loan can add up to thousands over time, so it pays to shop around.
The Moneysmart mortgage calculator can help you model different rates and terms. It shows that a shorter loan term means higher monthly payments but less interest overall, while a longer term eases monthly cash flow at the cost of more interest. Neither the calculator nor this article predicts your exact borrowing capacity—your lender’s full assessment is the only way to get a firm figure.
Setting Expectations (and Avoiding Surprises)
Remember that borrowing capacity estimates you see online are just that: estimates. They don’t account for all the nuances a lender will consider. Factors like the type of property, your employment stability, and even the number of dependants can all shift the final number.
OZ Home Loan provides general information to help you understand these concepts, but we’re not a lender and we don’t give personal financial advice. If you’d like to explore your options with a professional, we can help connect you to an Australian loan assistance enquiry within our scope. There’s no promise of approval, rate, or savings—just practical guidance for the next step.
Frequently Asked Questions
How does my credit score affect borrowing power?
A higher score can open access to more competitive loans and lenders, while a lower score may restrict your options or mean a smaller loan amount.
Can I use casual income to borrow?
Yes, but lenders typically apply a discount to casual or irregular income, often using only a portion of it in their calculations.
Does a bigger deposit always mean I can borrow more?
Not directly, but a larger deposit lowers the loan-to-value ratio (LVR), which can remove the need for Lenders Mortgage Insurance and demonstrate financial discipline.
What is the serviceability buffer?
It’s a requirement from APRA that lenders add 3% to the loan rate when assessing your ability to repay, ensuring you can handle future rate rises.
How can I improve my borrowing capacity?
Focus on reducing existing debts, managing living expenses, improving your credit score, and saving a larger deposit. Even small changes can make a difference in a lender’s eyes.