Borrowing power calculator
A conservative guide to how much you might borrow to buy or build, assessed the way a lender does, at a buffer rate well above the advertised one.
Last updated 14 June 2026
Borrowing power estimate
A quick guide to how much you might borrow. Lenders assess your repayments at a higher buffer rate than the advertised rate, so this is deliberately conservative.
$640,000
Estimate based on a 30 year term assessed at 8.6%. Actual capacity depends on your lender, deposit and full circumstances.
This is general information only and does not take into account your objectives, financial situation or needs. It is not credit assistance or a credit quote. Consider whether it is right for you and seek advice. Finance is arranged through Central Lending Solutions, the licensed credit partner The Property Plug works with (Australian Credit Licence or credit representative number [TBC]).
Got a number you are comfortable with?
See homes you can build for your budget →A borrowing power calculator estimates the maximum home loan you could service from your income after living costs and existing debts. The Property Plug calculator assesses your surplus at a lender-style buffer rate of about 8.6%, then converts it to a loan over 25 or 30 years. It is general information, not a credit approval.
What drives your borrowing power
Lenders do not lend a flat multiple of your income. They take your net income, subtract a benchmark for living costs and your existing commitments, then test whether the surplus could cover the repayment at a stressed rate. The bigger your surplus and the lower your debts, the more you can borrow.
- Net income, after an indicative tax estimate, drives the top line. Two incomes lift capacity but also raise the living allowance.
- The living allowance (HEM) scales with household size and dependants. Lenders use the higher of your real spending or the benchmark.
- Existing debts, including car and personal loans, reduce the surplus dollar for dollar.
- Credit card limits are assessed at about 3.8% of the limit per month, used or not.
- The assessment rate, typically the advertised rate plus a buffer near 3%, decides how much loan that surplus supports.
A Perth couple, dual income
Take a couple earning a combined $110,000 with no dependants, no other debts and no card limits. After an indicative net income and a two-adult living allowance, their monthly surplus services a loan in the low-to-mid $600,000s at an 8.6% assessment rate over 30 years. Drop the assessment rate or clear a $10,000 card limit and the number moves meaningfully, which is exactly the lever a broker tunes.
| Change | Effect on borrowing power |
|---|---|
| Close a $15,000 credit card | Frees about $570 per month of assessed commitment |
| Clear a $400 per month car loan | Adds roughly $50,000 to $60,000 of capacity |
| Add a second income | Lifts capacity, partly offset by a higher living allowance |
| Extend term 25 to 30 years | Increases the loan a given surplus supports |
Illustrative only. Effects vary by lender policy.
Read this before you rely on it
This calculator is general information, not a credit approval or a credit quote. It uses standard serviceability maths and indicative benchmarks, not any single lender's table. Real capacity depends on your lender, deposit, the property, your credit history and verified income. The right next step is a free call where we run your numbers against actual lender policy and find the lender whose rules suit your situation.
This is general information only and does not take into account your objectives, financial situation or needs. It is not credit assistance or a credit quote. Consider whether it is right for you and seek advice. Finance is arranged through Central Lending Solutions, the licensed credit partner The Property Plug works with (Australian Credit Licence or credit representative number [TBC]).
Why is the assessment rate higher than the advertised rate?
Lenders add a serviceability buffer (commonly around 3%) on top of the rate you would actually pay, to check you could still afford the loan if rates rose. APRA requires this. Our calculator defaults to an indicative 8.6% assessment rate, which you can change. It is why your borrowing power looks lower than a simple repayment sum suggests.
What is included in the living allowance?
Lenders apply a Household Expenditure Measure (HEM), a benchmark of typical living costs scaled by household size and income. Our tool uses an indicative HEM-style figure. If your real spending is higher than the benchmark, the lender uses the higher of the two, which can reduce your capacity.
Do credit card limits affect my borrowing power?
Yes, even unused ones. Most lenders assess about 3.8% of your total card limit as a monthly commitment, because you could draw it at any time. Reducing or closing cards before you apply can lift your borrowing power noticeably. Our calculator applies the same 3.8% rule.
Is this the amount a lender will approve?
No. This is an indicative guide using standard serviceability maths. Real approval depends on your lender, your deposit, the property, your credit history and full income verification. Treat the number as a starting point, then book a call so we can run it against actual lender policy.
See your real borrowing power
Book a free finance call. We run your numbers across lenders on our panel and find the one whose policy lends you the most for your build.