How much can I borrow on a $100k salary in Australia?
There's no single answer — a $100k salary doesn't map to one borrowing figure. Here's what actually moves the outcome, and where to get your number.
How much can I borrow on a $100k salary in Australia?
There isn’t one. Two people earning exactly $100,000 a year can be offered materially different loan amounts by the same lender, and that’s not a limitation of this article — it’s the accurate answer. What a lender will actually offer depends on your existing debts, how many dependants you support, your living expenses, the specific lender’s own policy, and a regulator-set buffer applied to the interest rate used in the assessment. Change any one of those and the number changes, sometimes by a lot. A salary figure alone was never going to produce a single reliable answer, and no lender publishes a formula that turns $100,000 into one.
Why doesn’t salary alone determine borrowing capacity?
Because Australian lenders aren’t allowed to lend on income alone. Under ASIC’s Regulatory Guide 209 (RG 209), a lender must make reasonable inquiries into both your income and your expenses, take reasonable steps to verify what you’ve told them, and assess whether you could meet the repayments without substantial hardship. Salary is one input into that test, not the test itself — see our guide to how banks calculate borrowing capacity for the full framework.
There is no formula this article — or any article — can complete for you. Identical salaries can produce meaningfully different borrowing outcomes once existing debts, dependants, expenses and a specific lender’s policy are all applied.
What actually moves the number for two people on the same salary?
None of the following comes with a published dollar effect — no authoritative source publishes one — but each is a genuine, verifiable input into the assessment:
| Factor | Why it changes the outcome |
|---|---|
| Existing debts and credit commitments | Tested against the buffered rate, reducing borrowing room |
| Dependants and household size | Raises assessed living expenses against a benchmark |
| Other income | Bonuses, overtime and rental income are usually discounted |
| Deposit size and loan-to-value ratio (LVR) | Smaller deposit, higher LVR, and LMI may apply |
| The lender’s own policy | Each lender runs its own serviceability calculator |
| The interest rate buffer | A regulator-set minimum margin applied to all debts |
None of these effects comes with a published dollar figure, but each is verifiable. Existing debts and credit commitments are tested against the assessed, buffered rate, which reduces what’s left over for a new mortgage; dependants and household size feed into the living-expenses side of the assessment, sense-checked against a benchmark like the Household Expenditure Measure (HEM). Non-salary income such as bonuses, overtime and rental income is generally discounted before it’s counted, per APRA’s guidance for lenders. A smaller deposit means a higher loan-to-value ratio (LVR); Moneysmart notes that lenders mortgage insurance (LMI) is usually payable once the amount borrowed exceeds 80% of the property value. The lender’s own policy and the interest rate buffer are covered in more detail below.
What is the interest rate buffer, and does it apply to me?
Yes — it applies to every home loan serviceability assessment, regardless of salary. Under Attachment C of Prudential Standard APS 220, Australian lenders must apply a buffer of at least 3.0 percentage points over the loan’s interest rate when testing whether you could afford it, and that buffer is applied to your existing debts as well as the new loan. It’s a regulator-set minimum, not a lender-specific figure, and it’s one of the reasons the same salary can support a smaller loan for someone who already carries other debt.
Does the type of lender or loan change the answer?
It can, but not in a way this article can quantify. APRA describes what it considers prudent serviceability practice — the interest rate buffer, discounting of non-salary income, use of expense benchmarks — in a practice guide (APG 223) that, by APRA’s own description, doesn’t itself create enforceable requirements; the enforceable minimum sits in the underlying prudential standard (APS 220). Within that space, individual lenders set their own credit policy, and that policy isn’t published. This article doesn’t assert what any named lender’s rules are, because no reliable source states them.
Where do I get an actual number for my situation?
From a lender or a licensed mortgage broker — that’s the only reliable source for a figure specific to you. A broker can run your actual income, debts, expenses and deposit position against more than one lender’s serviceability calculator and tell you where you land with each; a bank can do the same for its own policy. Both will apply the buffer and the income and expense treatment described above to your real numbers, not a generic salary.
The honest answer, restated
A $100,000 salary is one input into a multi-factor assessment, not an answer by itself. The genuinely useful response to “how much can I borrow on $100k?” is the list of what else determines it — not a number dressed up to look precise. If you want to understand the full assessment before you talk to a lender, see our guide to how banks calculate borrowing capacity, and for the deposit side of the picture, our guide to how much deposit you need for a first home in Australia.
