How Much Can I Borrow on a 100k Salary?

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If you are asking how much you can borrow on a 100k salary, the honest answer is that your income is only the starting point. Lenders across Australia assess what is left after tax, living costs and existing debts, then test whether you could still afford the loan if rates were three percentage points higher. This guide walks through that process in plain English, with worked examples you can adapt to your own numbers.

How lenders work out how much you can borrow

Lenders do not multiply your salary by a fixed number. They run a serviceability assessment, which looks at four things: your income after tax, your living expenses, your existing commitments, and the repayment on the new loan at an assessment rate. Under Australian Prudential Regulation Authority (APRA) guidance, that assessment rate must be at least 3 percentage points above the actual loan rate. We unpack that rule in more detail in our guide to the 3% serviceability buffer.

APRA also limits how much new lending a bank can write to borrowers with very high debt relative to income, known as the debt-to-income limit, which has applied since February 2026. For someone on $100,000 this is rarely the binding constraint, because the serviceability test usually bites well before total debt reaches six times income. For most single earners at this income, the serviceability test is what sets the ceiling.

What $100,000 looks like after tax

On 2025-26 resident tax rates plus the 2% Medicare levy, a $100,000 salary leaves roughly $77,000 a year, or about $6,400 a month. That is the figure a lender is really working with. From it they subtract your declared living expenses (they will not accept a number that looks unrealistically low, and most lenders benchmark against a household expenditure measure) and any debt commitments. What remains is your capacity to service a new loan, and different lenders land on different numbers for the same borrower. That is why two lenders can assess the same borrower tens of thousands of dollars apart.

Worked example: borrowing capacity on a 100k salary

The table below is illustrative only. It assumes a single borrower, a 30-year principal and interest loan, an actual variable rate of 6.6% and therefore a 9.6% assessment rate. The three scenarios differ only in the monthly repayment the lender decides you can afford after tax and expenses. Real lenders will arrive at their own figure, so treat this as a way to see how the maths moves.

Assessed monthly repayment capacity	Maximum loan at 9.6% assessment rate	Same repayment at actual 6.6% rate
$3,000	$353,707	$469,734
$3,500	$412,658	$548,023
$4,000	$471,609	$626,312

The third column shows why borrowers feel short-changed. The same monthly repayment would support a much larger loan at the rate you will actually pay, but lenders are required to use the higher figure. In the middle scenario, a $3,500 assessed capacity gives a maximum loan of about $412,000. If you then borrowed, say, $430,000, you would actually pay about $2,746 a month at 6.6%, compared with $3,647 at the assessment rate, so the buffer is a margin of safety rather than a repayment you are expected to make.

What reduces your borrowing power on a 100k salary

Small commitments carry a large weight because the assessment rate multiplies them over 30 years. Using the $3,500 scenario above, here is how common items change the result.

Credit cards

Lenders typically assume a repayment of around 3% of your total card limit every month, whatever the balance. A $10,000 limit therefore counts as roughly $300 a month, which lowers the example loan from about $412,658 to about $377,287, a drop of around $35,000. Closing or reducing unused limits before you apply is one of the cheapest ways to recover capacity.

HECS/HELP debt

Study debt reduces the repayment you can service because compulsory repayments come out of your pay. Under the 2025-26 marginal repayment thresholds published by the Australian Taxation Office (ATO), someone on $100,000 would repay roughly $4,950 a year, or about $412 a month. Deducting that from the $3,500 example lowers the loan to about $364,082, a reduction of roughly $48,600. Thresholds are indexed, so check the ATO for the rate that applies to your income year.

Dependants and expenses

Each child increases the living expense benchmark a lender applies, which shrinks the surplus. Genuine, documented expenses matter here, and a sloppy bank statement full of discretionary spending can cost you more than any debt.

Ways to borrow more on the same income

Because the assessment is mechanical, you can influence it before you apply. The checklist below covers the levers that tend to make a real difference.

• Reduce or cancel credit card limits you do not use.
• Pay out small personal loans, car loans and buy now pay later accounts where the numbers allow.
• Add a co-borrower. A second income usually raises capacity by more than their debts lower it, though not by a straight doubling.
• Choose a lender whose policy suits your income type. Bonuses, overtime and allowances are shaded differently from lender to lender.
• Reduce your expenses in the months before applying, so your statements back up the figure you declare.

Borrowing capacity is not the same as purchase price

A loan of $412,000 does not mean a $412,000 purchase. With a 20% deposit the loan is 80% of the price, so that loan supports a purchase of about $515,000, before stamp duty and costs. With a smaller deposit you may need to pay lenders mortgage insurance, which is added on top, and our explainer on how lenders mortgage insurance is calculated shows how that cost builds up. Stamp duty, legal fees and moving costs also come out of your savings, and each state and territory has its own concessions, so budget for them separately. You can also use our free mortgage tools to model repayments at different prices.

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