Beginner's Guide to Fixed Rate Investment Loans

Most fixed rate investment loans don't let you pay more than the required monthly amount without triggering break costs.

If you're weighing up whether to fix your investment loan or stay on a variable rate, the repayment flexibility question usually comes down to how you plan to use any surplus income. A variable rate loan gives you the option to throw extra cash at the loan whenever you want. A fixed rate typically doesn't, or caps how much extra you can contribute each year, often around $10,000 to $30,000 depending on the lender. Going over that limit can mean paying a break cost that wipes out any benefit you were hoping to gain.

For investors in Dubbo and across Central West NSW, this trade-off matters more than it does for owner-occupiers. Rental income can fluctuate with vacancy periods, and property expenses like rates, maintenance, and insurance all hit at different times of the year. If you've locked in a fixed rate and suddenly have $15,000 sitting in your offset account from a good rental run, you might not be able to move that money onto the loan without a penalty.

Why Investment Loans Are Usually Interest-Only

Most property investors choose interest-only repayments to keep their monthly costs down and maximise the deductions they can claim. When your loan is structured as interest-only, you're only paying the interest charged each month, not reducing the principal. That means your repayments are lower, your taxable rental loss is often higher, and you're preserving cash flow for other investments or to cover holding costs.

In our experience with investors holding properties around Dubbo, South Dubbo, and out towards Narromine or Wellington, keeping the loan interest-only for the first five to ten years is common. It lets you build a property investment strategy that relies on capital growth and tax efficiency rather than forcing you to pay down debt on an asset that's not your home. Once the interest-only period ends, the loan typically reverts to principal and interest unless you apply to extend it.

If you've fixed the rate, the same repayment restrictions apply whether you're on interest-only or principal and interest. You can't just decide to start making principal payments mid-term if the loan wasn't structured that way from the start. And if you're on interest-only, any extra repayments you're allowed to make under the cap will usually sit in a redraw or offset rather than reducing the loan balance, which can complicate your plans if you were hoping to lower your debt quickly.

Fixed Rate Extra Repayment Limits Across Lenders

Every lender sets their own rules. Some allow up to $10,000 in additional repayments per year without penalty. Others allow up to $30,000. A few major lenders don't allow any extra repayments at all during the fixed period. If you're comparing investment loan options, this detail often gets missed because the focus is usually on the advertised rate.

Consider an investor who fixed $450,000 at a low rate two years ago and now has $25,000 in cash they'd like to put towards the loan. If their lender caps extra repayments at $10,000 per year, they can only apply part of that amount. The rest either sits in an offset account earning no deduction benefit, or gets redirected to another property or investment. If they try to pay the full $25,000 onto the loan anyway, the lender will calculate a break cost based on the difference between the fixed rate they're contracted to and the current market rate. If rates have dropped since they fixed, that break cost can run into thousands of dollars.

How Break Costs Are Calculated

Break costs apply when you pay off more than your allowance during a fixed term, refinance, or sell the property before the fixed period ends. The lender is compensating for the income they lose when you exit the contract early. The calculation compares your fixed rate to the wholesale rate the lender can now get for the remaining term. If your rate is higher than the current wholesale rate, you'll usually pay the difference multiplied by the outstanding balance and remaining time.

If you're refinancing your investment loan to access better features or a lower rate, break costs can wipe out the benefit unless rates have risen since you fixed. We regularly see this with clients in Dubbo who locked in during a low rate period and are now looking to move lenders. The break cost isn't always obvious until the discharge is requested, and by that stage, the refinance is already underway.

Some lenders will waive or reduce break costs if you're moving the loan internally to another product within the same bank, but that's not guaranteed. If you've fixed with a smaller lender or non-bank, the calculation method and willingness to negotiate can vary significantly.

When Fixing Still Makes Sense for Investors

Locking in a fixed rate gives you certainty over your repayments and protects you if rates climb. If your rental income is tight and you're relying on that monthly cash flow to cover the mortgage, knowing exactly what the repayment will be for the next two to five years can make budgeting far more predictable, especially if vacancy rates in Dubbo tick up or you're carrying a property through a slower leasing period.

For investors who aren't planning to make extra repayments anyway, the lack of flexibility on a fixed rate isn't a drawback. If you're negatively geared and using the loss to reduce your taxable income, paying down the loan faster actually works against that strategy. You want to keep the debt high and the deductions flowing. In that scenario, a fixed rate without extra repayment capacity isn't a limitation, it's just irrelevant to how you're using the loan.

If you're holding multiple properties, splitting your loans so some are fixed and some are variable can give you the stability of a fixed rate on one property and the flexibility to make extra payments on another. That approach works well for investors with income that varies seasonally or who are planning to sell one property and want to funnel the proceeds into another without triggering break costs.

Split Rate Structures and How They Work

A split rate loan divides your total investment loan amount into two or more portions. You might fix 50% or 60% of the loan and leave the rest on a variable rate. Each portion operates independently, so the fixed portion has its own repayment terms and restrictions, while the variable portion lets you pay extra without penalty.

This structure is popular with Dubbo investors who want rate protection but don't want to lose all their repayment flexibility. If you've got $400,000 borrowed against a rental property, you could fix $240,000 for three years and leave $160,000 variable. Any surplus cash flow or lump sums can go onto the variable portion, and if rates drop during the fixed term, you're only locked in on part of the debt.

The downside is that managing two loans or splits adds a layer of administration. You'll have two sets of repayments, two rate reviews, and two sets of fees if you refinance or restructure. Some lenders charge a split loan fee upfront, and others limit how many splits you can have across your portfolio. If you're building wealth through property and plan to add more rentals over time, understanding how split structures fit into your overall borrowing is worth the conversation early.

Tax Treatment and Deductibility of Interest

All interest charged on an investment loan is generally tax-deductible, whether you're on a fixed or variable rate. But the way you structure repayments can affect your cash flow and your ability to claim other expenses. If you're making extra repayments on a fixed loan and those payments are sitting in redraw, the interest charged each month stays the same. That means your deductions don't drop, but your cash is tied up and not working elsewhere.

If you're thinking about paying down your investment loan faster to reduce interest costs, it's worth talking to your accountant about whether that aligns with your broader tax position. In some cases, keeping the investment debt higher and focusing any extra repayments on non-deductible debt like your home loan will give you a much stronger tax outcome. We regularly see investors who've been paying extra on the rental property for years, only to realise later that they've reduced their deductions and still have a large home loan that isn't giving them any tax relief.

The 2026 Federal Budget changes to negative gearing and capital gains tax don't affect the deductibility of interest on existing loans, but they do change the long-term appeal of established investment properties purchased after May 2026. If you're holding a property you bought before that date, your tax treatment continues under the old rules. If you're considering a new purchase, the way you structure the loan and your expected holding period both become more important to your after-tax return.

Refinancing Out of a Fixed Rate Early

If your circumstances change and you need to refinance before your fixed term ends, the break cost becomes unavoidable unless rates have moved in your favour. Refinancing can still be worthwhile if the new loan offers features that significantly improve your position, such as access to equity for another purchase, a better offset account, or the ability to consolidate debt.

In a scenario where you're refinancing to pull equity from a Dubbo investment property to fund a deposit on a second rental, the break cost is part of the transaction cost, just like stamp duty or conveyancing. If the equity release lets you proceed with a purchase that wouldn't otherwise be possible, paying a few thousand dollars in break costs might be the right call. But if you're refinancing purely for a slightly lower rate and the break cost is more than the interest saving over the next 12 months, it's usually not worth it.

Some lenders will let you port your fixed rate to a new property if you're selling one and buying another at the same time. That's rare, and the conditions are strict, but it's worth asking if you're in that position.

Call one of our team or book an appointment at a time that works for you. We'll walk you through your investment loan options and show you exactly how much flexibility you'd have with each lender, so you're not locked into a structure that doesn't fit how you actually use your money.

Frequently Asked Questions