Australia-wide · Finance & borrowing

Debt-to-income ratio & Borrowing Capacity in Australia

Know your number before you go to the bank.

Your debt-to-income ratio is one of the biggest things that decides how much you can borrow for property. Work it out before you apply, or you risk a knock-back that sets your plans back months.

Find your real borrowing capacity

What is a debt-to-income ratio?

Your DTI compares your total debt to your gross annual income, which is your income before tax. It gives a lender a fast read on how stretched your money is before they lend you more.

DTI = total debt ÷ gross annual income

For example, $900,000 of total debt on $150,000 income gives a DTI of 6.

Many Australian lenders treat a DTI of six or more as high. As your DTI climbs, they offer you less. Investors often face tighter limits again.

Here is the real risk. Most investors only find out their DTI is too high after they apply. By then they have lost time, bargaining power, and sometimes the property.

How debt affects borrowing capacity in Australia

Every debt you hold counts toward your DTI, even the ones you rarely use. So two people on the same income can end up with very different borrowing power. It comes down to how lenders assess borrowing capacity.

01

Credit cards

Lenders assess the full limit, not the balance. Unused limits still reduce your capacity.

02

Car loans

Fixed repayments lower the income left for future mortgage repayments.

03

Personal loans

Higher-rate, unsecured debt weighs heavily on serviceability.

04

Existing mortgages

Your current home and investment loans are counted in full as you scale.

How much can you borrow based on your DTI?

Multiply your gross income by your lender's DTI limit, then take off your current debts. That gives a rough ceiling for what you can borrow.

Real approval also looks at your living costs and a serviceability buffer. That buffer is a safety margin lenders add in case interest rates rise.

DTI4

Example A

Clean slate

$120k income, no debts. Limit is about $480,000. Most lenders are happy here.

DTI5

Example B

Personal loan

Same income plus a $60k personal loan. Only about $480k is left for a mortgage. The loan ate the rest.

DTI6

Example C

Existing mortgage

$150k income, $600k home loan. Total allowed debt is $900k. That leaves $300k for an investment loan.

DTI7+

Example D

Growing portfolio

Several properties push DTI over 7. Lenders tighten up. Options exist, but lender choice and structure matter far more.

These are examples, not your number. Two investors with the same DTI can get very different answers, based on the lender, the loan structure, and their plans. That is exactly what a clarity session maps out for you.

How a personal loan affects your debt-to-income ratio

Personal loans hurt more than most people expect. They are unsecured, meaning no asset backs them, so lenders treat them as riskier than a mortgage.

The repayments come straight off the income a lender counts. Even a small personal loan can drop your borrowing power for an investment property.

Want the detail? See our guide to the personal loan debt-to-income ratio. Clearing the loan before you apply often beats chasing a lower interest rate.

Converting your home to an investment property

When you move from owner-occupier to investment property, the lender treats your old loan as an investor loan. That usually means stricter rules.

Your rent helps you qualify, but lenders only count 70 to 80 per cent of it. They also test both loans against a higher safety rate.

01

Your DTI increases immediately

The full balance of your original loan is now investment debt. Rent only partially offsets this.

02

Rental income is discounted

Most lenders count only 70 to 80 per cent of your rent, to allow for empty weeks and costs.

03

Loan structure may need to change

A principal-and-interest owner-occupier setup may not be right once the property becomes a rental.

04

Timing affects your next application

Applying before or after the conversion produces different results. The sequence matters.

How to improve borrowing capacity

Your borrowing power is rarely fixed. A few smart moves before you apply can improve your borrowing power and lift what a lender will offer.

The goal is not just to lower your DTI. It is to lift your borrowing power without limiting your future investment opportunities.

01

Pay down high-rate debt

Clearing personal and card debt frees up serviceable income quickly.

02

Reduce credit card limits

Lowering or closing unused limits improves your DTI almost immediately.

03

Strengthen your income position

Stable, well-documented income helps lenders say yes with confidence.

04

Structure loans correctly

The right loan setup protects your capacity for future purchases.

Know exactly where you stand before you apply

Two investors can have the same DTI and get completely different results. It comes down to the lender, your loan structure, and your plans.

A calculator won't show you that. We map your real position and the moves that matter most for you.

This is where FPW is different. We weigh lender policy, your existing debt, your portfolio plans, and your loan structure together. So you see not just what you can borrow today, but how today's choices shape your next purchase.

Find your real borrowing capacity

Debt-to-income ratio for property investors

For investors, DTI is not a one-time hurdle. It shapes how far and how fast you can grow a property portfolio. Each property adds debt that counts in full. Without a plan, you can hit a wall after one or two buys.

The investors who keep growing plan their structure early. We help you see your DTI across the whole portfolio, not just the next loan. That turns borrowing power from a nasty surprise into part of your investment property strategy.

Common questions

Debt-to-income ratio FAQ

What is a good debt-to-income ratio?

Lower is better. Many Australian lenders treat a DTI of six or more as high. The right number depends on your income, the lender, and whether you are borrowing for a home or an investment property.

How much can I borrow based on my DTI?

Multiply your gross annual income by the DTI limit, then take off your current debts. On a $150,000 income at DTI 6, total debt can reach $900,000. A $600,000 mortgage leaves about $300,000 of room, before living costs and the safety buffer.

Does a credit card limit affect my borrowing capacity if I never use it?

Yes. Lenders assess the full limit, not the balance, so an unused card still reduces what you can borrow. Closing unused limits is one of the quickest ways to improve your position.

How does a personal loan affect a property application?

Personal loan repayments reduce the income a lender counts as available. Unsecured debt is also viewed as higher risk. Even a small personal loan can noticeably lower your borrowing capacity for an investment property.

How does DTI limit a property portfolio?

Each property adds debt counted in full. Without a plan, DTI can cap you after one or two purchases. Working with a property investment advisor helps you manage borrowing capacity across the whole portfolio.