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Understanding Your Borrowing Capacity

How lenders calculate how much you can borrow, and what you can do to maximize your borrowing power.

Last updated: January 2025

Understanding how much you can borrow is the crucial first step in your property journey. This guide explains how lenders calculate your borrowing capacity and what you can do to maximize it.

How Lenders Calculate Borrowing Capacity

Lenders use a formula that considers your income, expenses, and existing debts. The goal is to ensure you can comfortably afford repayments.

Key Factors

  • Gross income: Your total income before tax from all sources
  • Living expenses: The higher of your declared expenses or HEM benchmarks
  • Existing debts: Car loans, personal loans, HECS/HELP
  • Credit card limits: Even if you don't use them!
  • Dependants: Children increase expense allowances

The Assessment Rate Buffer

Lenders don't assess your ability to repay at the actual interest rate. They add a buffer (typically 3%) to ensure you can handle rate rises.

Example: If the loan rate is 6%, they'll assess at 9%.

This is why online calculators often show higher borrowing than what you actually qualify for.

The Credit Card Trap

Lenders assume you could max out your credit cards at any time. A $10,000 limit reduces your borrowing by approximately $50,000—even if the balance is zero. Close unused cards or reduce limits before applying.

Ways to Increase Your Borrowing Capacity

  1. Reduce credit card limits: Cancel unused cards or lower limits
  2. Pay off small debts: Clear personal loans and car finance
  3. Reduce expenses: Cut discretionary spending in the months before applying
  4. Joint application: Applying with a partner combines incomes
  5. Choose the right lender: Different lenders have different policies
  6. Longer loan term: 30 years vs 25 years increases capacity (but costs more long-term)

Single vs Joint Applications

Applying jointly typically increases borrowing capacity because:

  • Two incomes are considered
  • Living expenses don't double (economies of scale)

However, both applicants' debts and credit history are also considered.

Why Different Lenders Give Different Answers

Not all lenders calculate serviceability the same way. Differences include:

  • How they treat overtime, bonuses, and commission
  • Expense benchmarks used
  • Treatment of rental income
  • Credit score requirements

This is why using a broker matters—we know which lenders suit different situations.

What Doesn't Affect Borrowing Capacity

  • Your savings (except for deposit purposes)
  • Your age (within reason)
  • Property location
  • Property type (usually)

Next Steps

Want to know your actual borrowing capacity?

  1. Use our borrowing calculator for an estimate
  2. Book a free consultation for an accurate assessment

Ready to Take the Next Step?

Book a free consultation to discuss your mortgage needs with our expert team.

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