How Much Can I Borrow? What Perth First Home Buyers Need to Understand

"How much can I borrow?" is usually the first question first home buyers ask — and one of the most misunderstood. Online calculators give you a number in seconds, but that number can be very different from what a lender will actually approve. Here's what borrowing capacity really means, what determines it, and why the number alone doesn't tell the full story.

Borrowing Capacity vs Loan Approval — They Are Not the Same Thing

This is the most important distinction for any first home buyer to understand.

Borrowing capacity is a calculation — a theoretical maximum based on your income, debts, and expenses assessed against a lender's criteria. An online calculator will give you a figure, and some lenders will provide an indicative capacity quickly.

Loan approval is a decision — based not just on your capacity, but on your deposit size, the property itself, your credit profile, your employment type, and the specific policies of the lender you're applying to.

⚠ A common misconception

Many buyers assume that if a calculator says they can borrow $700,000, they'll be approved for $700,000. In practice, lenders apply a serviceability buffer (currently around 3% above the loan rate), assess expenses conservatively, and may limit lending based on the property's location, your deposit size, or your employment type. The approved amount is often lower than the calculated capacity.

The Five Factors That Determine How Much You Can Borrow

1. Your Income

The starting point for any capacity calculation is your gross income — salary, wages, or assessable self-employment income. But not all income is treated equally.

• Base salary (PAYG) — accepted at full value by most lenders

• Overtime and bonuses — often accepted at 50–80% of the average over 12–24 months, depending on consistency

• Casual and contract income — typically requires 12 months of history in the same role or industry

• Self-employment income — usually assessed on your net profit after tax deductions over two years

• Rental income (if applicable) — accepted at around 70–80% of gross rent by most lenders.

  
  

2. Your Existing Debts

Every debt you carry reduces your assessed borrowing capacity — often by more than you'd expect. This includes:

• Credit card limits (not balances — the limit is what counts)

• Personal loans and car loans

• HECS/HELP student debt

• Buy Now Pay Later accounts

• Any other existing mortgages or guarantor obligations

A practical example

A $10,000 credit card limit can reduce your borrowing capacity by approximately $50,000–$60,000, because lenders assume you could draw the full limit at any time. Closing an unused credit card before applying can meaningfully increase what you're able to borrow.

3. Your Living Expenses

Lenders are required to assess your actual living expenses — not just use an industry benchmark. They'll analyse three to six months of bank statements to understand your spending patterns: groceries, utilities, subscriptions, dining, transport, and discretionary spending.

In recent years, lenders have become more thorough in this assessment. If your expenses are higher than the benchmark figure, they'll use yours. If lower, they may still apply the benchmark as a floor. Keeping your spending disciplined in the months before application can make a meaningful difference.

4. The Interest Rate Buffer

This is one of the most significant — and least understood — factors in capacity calculations. Lenders are required by APRA (the banking regulator) to assess your ability to repay the loan at the contracted rate plus a 3% buffer. If your actual rate is 6.2%, they'll test your repayments at 9.2%.

This buffer exists to ensure you can still afford repayments if rates rise — but it significantly reduces what you can borrow relative to what the repayments would actually be at today's rate.

5. Your Deposit and LVR

Your deposit size affects borrowing capacity indirectly by determining your Loan-to-Value Ratio (LVR). A higher LVR (smaller deposit) can trigger additional lender restrictions — including postcode limitations, lower maximum loan amounts, and in some cases, a higher assessed rate.

A broker can model your capacity across multiple lenders — the difference in what you can borrow can be significant depending on the lender chosen.

Why Different Lenders Give Different Answers

One of the most surprising things for first home buyers is that the same borrower can receive significantly different capacity figures from different lenders — sometimes varying by $100,000 or more.

This happens because each lender has their own:

• Expense benchmarks (known as HEM — Household Expenditure Measure)

• Policies on income types (particularly casual, overtime, and self-employed income)

• Treatment of HECS debt and BNPL accounts

• Postcode policies for high-density areas or regional locations

• Maximum LVR policies at different loan sizes

This is one of the primary reasons working with a broker — rather than applying directly to a single bank — can produce a meaningfully better outcome. A broker can identify which lender's policies best match your specific income profile and financial situation.

Borrowing Capacity vs What You Should Borrow

This is a conversation that often gets skipped — and it shouldn't.

Just because a lender will approve you for $700,000 doesn't mean borrowing $700,000 is the right decision. Lenders assess whether you can service the loan — they don't assess whether you'll be comfortable doing so.

"Borrow what the bank will approve — but buy what you can comfortably live with. The gap between those two numbers is where financial stress lives."

A good broker will discuss both numbers with you: the maximum the lender will approve, and the repayment amount that fits comfortably within your actual budget, lifestyle, and goals.

Ways to Increase Your Borrowing Capacity Before Applying

Reduce credit card limits Close unused cards or reduce limits. Each $10,000 in credit card limit removed can increase your borrowing capacity by $50,000+.	Pay down personal loans Eliminating a car loan or personal loan before applying removes the liability from your assessment entirely.
Tidy your bank statements Reduce discretionary spending in the 3 months before application. Avoid gambling transactions, frequent cash withdrawals, and large irregular expenses.	Choose the right lender Different lenders treat income types, HEM benchmarks, and HECS debt differently. The right lender for your profile can make a significant difference to your approved amount.

What to Expect When You Work With a Broker

Rather than giving you a generic estimate, a broker will gather your actual financial details — income, debts, expenses, deposit — and run an accurate assessment across multiple lenders. You'll get a realistic picture of your capacity, which lenders are most likely to approve you, and what you can do to strengthen your position if needed.

This takes one conversation and replaces hours of guesswork with a clear, accurate number you can actually plan around.

Want to know your real borrowing capacity?

Skip the generic calculators. Book a strategy session and get an accurate assessment based on your actual numbers — including which lenders will work best for your situation.