Beginner's guide to fixed rate investment loans

Fixed rates lock in your borrowing cost but change how extra repayments work

A fixed rate investment loan protects you from interest rate movements for a set period, usually between one and five years. That certainty can help when you're planning cash flow around a rental property, particularly in an area like Tarneit where many investors are holding properties for long-term portfolio growth. The catch is that most fixed rate products limit how much extra you can repay each year without triggering break costs, and some block extra repayments entirely.

When you fix the rate on an investment loan, the lender prices that contract based on what they expect interest rates to do over the fixed period. If you repay early or pay more than the allowed limit, the lender loses the interest income they were counting on and may charge you the difference.

How much can you repay on a fixed investment loan?

Most lenders allow between $10,000 and $30,000 in extra repayments per year during a fixed period, though some allow nothing at all. The limit usually resets each anniversary. If you exceed the cap, you'll be charged break costs, which are calculated based on the lender's funding cost and the remaining term. Those costs can run into thousands of dollars if rates have dropped since you fixed.

Consider an investor who purchased a townhouse in Tarneit's Newgate Estate and fixed their loan at 6.2 per cent for three years. Rental income from the property was strong, and they decided to put an extra $40,000 toward the loan in the first year to reduce debt faster. Their lender allowed $20,000 in extra repayments without penalty, but the remaining $20,000 triggered break costs of around $3,200 because rates had fallen since the loan was fixed. That cost wiped out much of the benefit they were hoping to gain.

If you're holding a rental property in a growth corridor and expect irregular lump sums from bonuses, tax refunds or other income, check the extra repayment limit before you fix. Some lenders let you nominate a higher limit upfront in exchange for a slightly higher rate. That can make sense if you know you'll want flexibility down the track.

Interest-only fixed loans and the question of paying down principal

Many property investors in Tarneit choose interest-only repayments to keep their deductible interest as high as possible and free up cash for other investments or deposits on additional properties. When you fix an interest-only loan, extra repayments still count against your annual cap, but they reduce the principal balance, which in turn reduces the interest you're charged.

That sounds useful, but it can create a tax problem. If you pay down the loan principal using non-deductible income and later redraw that money for private purposes, the interest on the redrawn portion is no longer deductible. Many lenders also block redraws entirely during a fixed period, so any extra repayment you make is locked away until the fixed term ends.

In our experience, investors who fix on interest-only terms usually do so because they want certainty around cash flow, not because they want to accelerate principal reduction. If your goal is to pay down the loan faster, a variable rate with an offset account gives you more control.

Variable and fixed split structures

Some borrowers split their loan between variable and fixed portions. You might fix 60 per cent of the balance for rate certainty and leave 40 per cent variable for flexibility. Extra repayments go to the variable portion, where there are no break costs and you can usually redraw if needed. The fixed portion gives you protection if rates rise, and the variable portion lets you reduce debt faster when you have surplus cash.

This structure works particularly well for investors in Tarneit who are balancing rental income from a new estate property with fluctuating household expenses. Tarneit's rental vacancy rate has stayed low due to strong demand from families moving into the area, so rental income is typically reliable. A split loan lets you lock in part of your repayment while still putting extra funds toward the loan when tenants renew or you receive a tax refund.

You can usually set the split however you like, as long as each portion meets the lender's minimum balance, which is often around $50,000. Some lenders will let you adjust the split at the end of the fixed term, so you're not locked into the original structure for the life of the loan.

Offset accounts on investment loans

An offset account linked to a variable investment loan reduces the interest you're charged without reducing the loan balance itself. That keeps your borrowing capacity intact if you want to access equity later, and it doesn't create the same tax complications as paying down principal and redrawing.

Most lenders don't offer offset accounts on fixed rate investment loans, though a few do. When they're available, the rate is usually higher than a standard fixed product, often by 0.2 to 0.4 percentage points. The offset still works the same way, it just costs more to set up.

If you're deciding between fixing with a limited extra repayment cap or staying variable with a full offset, the choice depends on how much surplus cash you expect to hold and how much you value rate certainty. Investors with steady rental income and limited surplus often prefer to fix. Investors with irregular income or larger cash reserves tend to favour variable with offset.

How the negative gearing changes affect fixed versus variable decisions

From 1 July 2027, rental losses on most residential properties purchased after 12 May 2026 will be quarantined and can only be offset against rental income or carried forward. That makes cash flow planning more important, because you can't use a rental loss to reduce your tax on salary or other income.

A fixed rate loan gives you certainty around your interest cost, which is now your main deductible expense. If you're buying an investment property in Tarneit after mid-2026, fixing part or all of your loan might make it easier to forecast whether the property will be cash flow positive or how large a shortfall you'll need to fund from other sources. The downside is that you lose flexibility to make extra repayments, which could help you reach positive cash flow sooner.

Properties that qualify as eligible new builds under the legislation retain full negative gearing and the CGT discount. Most of the new developments in Tarneit's northern and western growth precincts fall into that category, because they're being built on previously vacant land. If you're buying one of those properties, the tax treatment is unchanged, and your decision between fixed and variable comes down to rate expectations and cash flow preferences rather than tax planning. You can read more about how investment loan features vary by lender on our investment loans page.

When break costs apply and how they're calculated

Break costs are charged when you repay more than your annual limit, refinance, or sell the property before the fixed term ends. The lender calculates the cost by working out how much income they'll lose compared to what they could earn by lending that money elsewhere at current wholesale rates. If rates have fallen since you fixed, break costs will be high. If rates have risen, break costs are usually zero because the lender can reinvest your repayment at a better rate.

You won't know the exact break cost until you ask for a payout figure, because the calculation depends on the rate environment at that moment. Some lenders publish break cost calculators on their website, but the formula varies between lenders and isn't standardised.

If you think you might sell or refinance within the fixed period, either avoid fixing altogether or choose a shorter fixed term so you're less likely to be caught with a large break cost. Alternatively, fix only part of your loan and keep the rest variable so you can repay or refinance the variable portion without penalty.

Choosing the right product when you're buying in Tarneit

Tarneit is one of Melbourne's fastest-growing suburbs, with a large proportion of new housing stock and strong demand from young families. Most investment properties in the area are townhouses or units in master-planned estates, and rental yields sit in the mid-4 per cent range at current pricing. If you're purchasing an investment property here, your loan structure should reflect both the rental income you're likely to receive and the growth outlook for the suburb.

A fixed rate makes sense if you want certainty and don't expect to have large amounts of surplus cash to put toward the loan. A variable rate or split structure makes more sense if you're planning to grow your portfolio over the next few years and want to preserve flexibility to access equity or make extra repayments. We regularly see investors in Tarneit who start with a fixed loan and then move to variable or split when they refinance at the end of the fixed period, once they have a clearer view of their cash flow and growth plans.

Call one of our team or book an appointment at a time that works for you. We'll walk through your situation, your rental income projections, and which loan structure gives you the right mix of certainty and flexibility for where you're at now.

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