Beginner's Guide to Borrowing Capacity for Nurses

Your borrowing capacity determines how much a lender will approve, not how much deposit you've saved.

Most registered nurses earn base salary plus penalty rates, overtime, and shift allowances, and the way lenders treat those components changes your approved loan amount by tens of thousands of dollars. Some lenders assess penalty rates at 100 percent of their value. Others discount them to 80 percent or ignore them entirely. Your borrowing capacity is the maximum loan amount a lender will approve based on your income, expenses, existing debts, and a serviceability buffer. The buffer adds a margin above the current interest rate to test whether you could still afford repayments if rates rise. That buffer sits between 2.5 and 3 percent depending on the lender, and it operates as a hard ceiling on how much you can borrow regardless of your deposit size.

How Lenders Calculate Your Net Income

Lenders calculate your borrowing capacity by first determining your net income after tax, superannuation, and other deductions. They then subtract your committed monthly expenses, including rent, groceries, transport, insurance, childcare, HECS debt repayments, credit card limits, and any other loan repayments. What remains is your surplus income, and that surplus must be large enough to service the proposed home loan repayment plus the serviceability buffer. If your surplus falls short, the lender reduces the approved loan amount until the repayment fits within your capacity.

Consider a registered nurse earning a base salary of $85,000 plus $18,000 in penalty rates and allowances. If the lender assesses the full $103,000, the borrowing capacity might reach $580,000. If the same lender discounts the penalty component to 80 percent, the assessed income drops to $99,400 and the approved loan amount falls to around $550,000. The $30,000 difference in borrowing capacity is the direct result of how that lender treats shift income, not a reflection of affordability or risk.

We regularly see nurses who have been pre-approved by a major bank at one figure, only to discover that a different lender using a more favourable income assessment method would approve them for $50,000 to $80,000 more. The nurse's financial position has not changed. The lender's policy has.

What Counts as Income and What Doesn't

Base salary, regular overtime, penalty rates, shift allowances, and other recurring payments are generally included in your income assessment, subject to the lender's specific policy on each component. Bonuses, reimbursements, and irregular payments are usually excluded unless they have been paid consistently for at least two years and the lender can verify they will continue. If you work as a casual or agency nurse, lenders typically require at least six to twelve months of continuous employment with the same employer or agency before they will assess your income, and they will average your earnings over that period rather than annualising your most recent payslip.

A midwife working permanent part-time at 0.8 FTE with a base salary equivalent to $90,000 full-time earns $72,000 base plus penalty rates. If penalty rates add another $14,000 annually and the lender counts them at 100 percent, the assessed income is $86,000. If the lender discounts penalties to 80 percent, the assessed income falls to $83,200. The $2,800 difference in assessed income translates to roughly $15,000 to $18,000 in borrowing capacity depending on the applicant's other commitments.

Rental income from an investment property is assessed differently. Lenders typically assess rental income at 80 percent of the gross rent to account for vacancy periods, maintenance, and property management fees. If you own an investment property generating $650 per week in rent, the lender will assess $520 per week as income and treat the mortgage repayment, strata fees, council rates, and insurance as expenses. The net position either adds to or subtracts from your borrowing capacity depending on whether the property is positively or negatively geared.

The Serviceability Buffer and Why It Matters

The serviceability buffer is an additional margin added to the current interest rate to test whether you could still afford repayments if rates increase. Most lenders apply a buffer of 3 percent, meaning if the current variable rate is 6.5 percent, the lender will test your capacity to service the loan at 9.5 percent. Some lenders use a floor rate instead, assessing serviceability at a minimum rate regardless of the actual product rate. If the floor is set at 9 percent and your discounted variable rate is 6.2 percent, the lender still tests you at 9 percent.

This buffer is the reason borrowing capacity has fallen since interest rates began rising. A nurse who could borrow $650,000 when the cash rate was 0.1 percent might now be approved for $480,000 with the same income and expenses, purely because the serviceability buffer is applied to a higher base rate. The buffer does not appear on your loan documents and does not affect your actual repayment. It exists only as a stress test within the lender's assessment model.

For nurses working at hospitals in outer metropolitan areas like Blacktown or Liverpool, where property prices sit below the metro median, the serviceability buffer has less impact because the loan amount required is smaller relative to income. A nurse earning $95,000 seeking a $500,000 loan will pass the buffer test comfortably. The same nurse seeking a $750,000 loan to buy near Randwick or Kogarah may not, even with a larger deposit, because the repayment at the buffered rate exceeds their surplus income.

Living Expenses and the HEM Benchmark

Lenders use either your declared living expenses or a benchmark figure called the Household Expenditure Measure (HEM), whichever is higher. The HEM is calculated by the Melbourne Institute and provides a standardised estimate of basic living costs based on household size, income, and location. If you declare $2,800 per month in living expenses but the HEM for your household type is $3,200, the lender will use $3,200 in the assessment.

A single nurse renting in Footscray and declaring $2,500 per month in expenses might find the lender applies a HEM figure of $2,900 instead. That additional $400 per month reduces borrowing capacity by approximately $80,000 to $90,000. If you have dependants, the HEM rises significantly. A nurse with two school-age children will face a HEM benchmark that is $1,000 to $1,500 per month higher than a single applicant with the same income, and that difference directly reduces how much they can borrow.

You cannot negotiate the HEM. It is applied automatically by the lender's assessment system. The only way to offset it is to reduce discretionary expenses, pay down existing debts, or increase your assessed income by moving to a lender that treats penalty rates more favourably.

Credit Card Limits and How They Reduce Capacity

Lenders assess your credit card limit as a monthly expense even if you pay the balance in full each month and never pay interest. The calculation assumes you could draw the full limit at any time, and the lender applies a repayment rate of 3 to 3.5 percent of the limit as a recurring monthly cost. A credit card with a $15,000 limit is treated as a $450 to $525 monthly expense regardless of your actual usage.

If you hold three credit cards with combined limits of $35,000, the lender will deduct approximately $1,050 to $1,225 per month from your surplus income. That reduction in surplus lowers your borrowing capacity by $200,000 to $240,000 depending on the lender and the interest rate. Closing unused cards or reducing limits before you apply for a home loan pre-approval can add six figures to your approved loan amount without any other change to your financial position.

We regularly see this with nurses who have held store cards, interest-free purchase plans, or secondary credit cards they no longer use. The cards were opened years ago and forgotten, but the limits remain active on their credit file. A nurse practitioner earning $120,000 with $40,000 in unused credit limits might be approved for $680,000. The same applicant with those limits closed could be approved for $880,000. The difference is not theoretical. It is the direct mechanical result of how the lender's serviceability calculator operates.

HECS Debt and Income-Contingent Loans

HECS-HELP debt is treated as an expense based on a percentage of your gross income, not the outstanding balance. The repayment rate varies depending on your income bracket, and the lender applies that rate as a recurring monthly deduction. A nurse earning $95,000 with a HECS debt of $45,000 will have a repayment obligation of approximately $400 to $450 per month deducted from their surplus income. The size of the debt does not matter. The repayment obligation is calculated from your income, and it reduces borrowing capacity by roughly $80,000 to $90,000.

If you have multiple income-contingent loans such as HECS, SFSS, or TSL, the lender aggregates the repayment obligations and treats them as a single combined expense. Paying down HECS debt does not improve your borrowing capacity unless the repayment drops you into a lower income threshold where the percentage rate falls. In most cases, using surplus savings to reduce other debts such as car loans or credit cards will have a larger impact on borrowing capacity than paying down HECS.

How Lenders Treat Agency and Casual Work

Agency and casual nurses are assessed using an average of their last six to twelve months of income, and lenders require evidence that the work is ongoing. If your payslips show irregular hours or gaps in employment, the lender will either exclude those periods or apply a discount to the averaged income. A casual nurse who earned $110,000 over the past twelve months but took eight weeks unpaid leave will have that period excluded, and the assessed income will be based on the remaining forty-four weeks.

Some lenders require a letter from the agency or employer confirming that shifts will continue to be offered. Others will assess casual income only if you have been with the same agency for at least twelve months and can demonstrate consistent rostering patterns. If you work across multiple agencies, most lenders will assess each income stream separately and apply the stricter casual income policy to each.

For nurses considering a move from permanent to agency work, the borrowing capacity impact can be significant. A permanent nurse earning $95,000 will generally be assessed at that figure with no discount. The same nurse moving to agency work and earning $105,000 may be assessed at only $90,000 to $95,000 because the lender applies a stability discount to casual income, even if the total earnings are higher.

Why Different Lenders Approve Different Amounts

Each lender uses a different serviceability model, and the approved loan amount for the same applicant can vary by $100,000 or more depending on which lender assesses the application. The variables include how penalty rates are treated, what buffer or floor rate is applied, how the HEM is calculated, and whether the lender applies additional overlays for specific occupations or postcodes.

A nurse earning $98,000 applying to Lender A might be approved for $620,000. The same nurse applying to Lender B might be approved for $530,000. The difference is not a reflection of credit quality or risk. It is the result of Lender A counting penalty rates at 100 percent and using a 2.5 percent buffer, while Lender B discounts penalties to 80 percent and uses a 3 percent buffer. Both lenders are applying their own policies correctly. The outcomes are simply different.

This is why working with a mortgage broker who understands how each lender treats healthcare income changes the outcome. A broker who knows which lenders assess shift penalties at full value can direct your application to the panel that will approve the highest amount. A broker who does not have that knowledge will send your application to whichever lender they use most often, and you will be approved for whatever that lender's model produces.

Improving Your Borrowing Capacity Before You Apply

The fastest way to increase borrowing capacity is to reduce committed expenses. Close unused credit cards, pay out small personal loans, and reduce your credit card limits to the minimum you actually need. Each $10,000 reduction in credit limits adds approximately $50,000 to $60,000 in borrowing capacity. Paying off a $15,000 car loan adds another $90,000 to $100,000.

If you rent, reducing your rent by moving to a lower-cost property or taking on a housemate can add $40,000 to $60,000 in capacity for every $100 per week you save. If you pay childcare, moving to a family arrangement or reducing days in care has the same effect. The lender does not care why your expenses are lower. They care only that your surplus income is higher.

For first home buyers who are still saving a deposit, the order of priority is clear: pay down high-interest debt first, reduce or close credit facilities second, and build your deposit third. A nurse with $30,000 saved, $8,000 in credit card debt, and $12,000 owing on a car loan will improve their borrowing capacity more by clearing the debts than by adding the $20,000 to their deposit. The lender will approve a higher loan amount with a smaller deposit if your surplus income is stronger.

Call one of our team or book an appointment at a time that works for you. We work exclusively with nurses and midwives, and we know which lenders will approve you for the highest amount based on how your income is structured.

Frequently Asked Questions