A pay rise can improve your borrowing capacity, but a new car lease, higher childcare costs or a credit card limit can pull it back just as quickly. When clients ask which expenses reduce borrowing power, the answer is rarely one single bill. Lenders assess the combined picture of your income, existing commitments, household spending and the repayment buffer they must apply before approving a loan.
For Australians planning to buy a home, grow an investment portfolio or refinance for a better structure, understanding this assessment can prevent an unwelcome gap between an online calculator estimate and a lender's formal approval.
How lenders assess borrowing power
Borrowing power is broadly the amount a lender believes you can repay while still meeting your regular financial obligations. It is not simply your income less your current mortgage or rent. Each lender applies its own servicing policy, expense benchmarks and interest-rate buffer, so outcomes can vary materially from one bank to another.
Most lenders start with verified income, then subtract known commitments and reasonable living expenses. They test the proposed loan repayment at a higher assessment rate rather than the advertised rate. This buffer is designed to show that the loan remains affordable if rates rise or household circumstances change.
Your bank statements, credit report, payslips and tax returns may all inform the result. A lender is not looking for a perfectly lean household budget. It is looking for a credible, sustainable position that leaves enough surplus after every ongoing commitment is counted.
Which expenses reduce borrowing power?
The expenses with the greatest impact are generally fixed, recurring and contractual. They are difficult to stop quickly, so a lender must assume they will continue throughout the loan term or for a meaningful period of it.
Existing debts and loan repayments
Home loans, investment loans, car finance, personal loans, HELP debts and business loans can all reduce serviceability. For an existing mortgage, the lender may assess the repayment at its buffered rate, not at the rate you currently pay. This can make the assessed commitment significantly higher than the amount leaving your account each month.
Car finance is often underestimated. A modest-looking monthly repayment on a new vehicle can reduce capacity because it is a fixed commitment over several years. The same applies to personal loans used for renovations, weddings or consolidating debt. Clearing a small balance before applying may make a larger difference than borrowers expect, particularly where the repayment is high relative to the remaining balance.
For investors and business owners, the position can be more nuanced. Existing lending may be supported by rental income or business income, but lenders often shade that income for vacancies, expenses or volatility. The structure of the debt matters as much as the headline balance.
Credit cards, charge cards and buy now, pay later accounts
Credit card limits can affect borrowing power even when you pay the balance in full each month. Rather than assessing only what you owe today, many lenders apply a monthly repayment percentage to your total approved limit. A $15,000 card limit may therefore be treated as an ongoing commitment whether the card balance is nil or not.
Reducing or cancelling unused limits can be a practical pre-application step, provided it suits your broader cash-flow needs. Store cards, charge cards and buy now, pay later facilities also need to be disclosed. Their treatment varies by lender, but regular repayments and multiple facilities can raise questions about household cash flow.
Childcare, school fees and family commitments
Childcare is one of the most significant household expenses in a lender's assessment because it can be both substantial and unavoidable. The actual amount may be used when it exceeds the lender's standard living-expense benchmark. For households with young children, this can materially change borrowing capacity.
Private school fees, child support, maintenance obligations and regular financial support for dependants also need to be factored in. Some expenses may reduce in the future - for example, childcare once a child starts school - but lenders will only give weight to that change where their policy allows it and the timing is well supported.
Living expenses and discretionary spending
Lenders use household expenditure measures as a starting point, but your actual spending can take precedence where it is higher. This is why six months of statements deserve a careful review before a loan application.
Regular spending on groceries, utilities, insurance, fuel, medical costs and mobile plans is expected. The issue is not that a household spends money on normal life. The issue is when discretionary spending is high, inconsistent with declared figures, or leaves little evidence of surplus income.
Dining out, subscriptions, travel, gambling transactions, frequent rideshare use and large retail purchases can all be visible in transaction data. One-off costs are not necessarily a problem. A pattern of recurring expenditure is more likely to influence the lender's view of affordability.
Investment property holding costs
Property investors need to account for more than the loan repayment. Rates, strata levies, landlord insurance, property management fees, maintenance and potential vacancy periods all affect the true holding cost of an investment property.
Lenders commonly discount rental income rather than using 100 per cent of the rent received. That conservative approach means a property that appears cash-flow neutral in real terms may still reduce serviceability on paper. This does not make the investment unsuitable, but it does make lender selection and loan structure more important before the next acquisition.
Business and self-employed commitments
For business owners, personal and business finances are often more connected than they first appear. Equipment finance, commercial property debt, director guarantees, business credit cards and lease obligations may be considered in a personal application, depending on the structure and lender policy.
A business expense that is genuinely deductible or paid by the company may not be treated the same way as a personal commitment. However, the lender will want to see that the business can meet its obligations without placing pressure on your personal income. Clean financials, sustainable profit and a clear explanation of one-off expenses are particularly valuable here.
Expenses that may be treated differently
Not every outgoing has an identical effect. Some lenders use actual repayments for certain debts, while others use a higher calculated minimum. Some accept a portion of overtime, bonuses, commission or rent; others apply more conservative shading. The same is true for family benefits, investment income and business profits.
Rent is another common point of confusion. Paying rent demonstrates an existing housing cost, but it does not necessarily reduce capacity dollar for dollar once you buy a home. In many assessments, the new proposed mortgage repayment replaces the rental commitment. Timing matters, though. If you will retain a rental property or overlap rent and mortgage payments temporarily, that needs to be planned for.
Practical ways to improve your position before applying
The goal is not to cut every enjoyable expense or manipulate your statements for a few months. It is to present a financial position that is genuinely manageable after settlement. Start by identifying commitments that no longer serve a purpose, such as unused credit limits, dormant buy now, pay later accounts or high-cost personal debt.
If possible, avoid taking on new finance shortly before applying for a home loan. A new vehicle loan or consumer purchase can change servicing calculations immediately. Keep repayments on time, as credit conduct matters alongside affordability, and make sure declared expenses align with the evidence in your accounts.
For a couple, decide early whether both incomes and liabilities will be included. Adding an applicant can increase income, but their debts, dependants and spending also form part of the assessment. For investors, a review before signing a contract can clarify whether the next purchase should be held personally, through a trust or within a broader lending structure. The right approach depends on lending policy, tax advice, asset protection considerations and your longer-term acquisition plans.
Why strategy matters more than a single calculator result
Borrowing capacity calculators are useful for an initial range, but they cannot fully capture different lender policies or a complex financial position. This is especially true for self-employed borrowers, investors with multiple properties, clients receiving variable income, and business owners with several facilities.
A strategic lending review can identify which commitments are genuinely limiting your capacity, which can be refinanced or repaid, and which lenders may assess your income and expenses more favourably. The Finance Office helps borrowers consider that wider structure before they commit to a purchase or loan application.
Before setting a property budget, review your last few months of spending as a lender would. The clearest pathway to stronger borrowing power is usually not a dramatic sacrifice - it is removing unnecessary commitments, documenting your income properly and choosing a lending structure that supports the next stage of your plans.
