Rate Lock-ins and Break Costs: The Risks and Rewards

A fixed rate on an investment loan locks in your repayments for a set period, but it also locks you into a contract that can cost thousands to exit.

If you're considering fixing part or all of your investment loan, you need to understand what you're signing up for. A fixed rate protects you from rising interest rates, but it removes flexibility. If you need to sell the property, refinance for a lower rate, or access equity before the fixed term ends, the lender will charge break costs to compensate for the interest they expected to earn from you.

The question isn't whether to fix or stay variable. It's whether you can afford to be locked in.

How a Fixed Rate Lock-in Works

When you fix your investment loan, the lender commits to a specific interest rate for a set period, typically one to five years. You commit to making repayments at that rate, regardless of what happens to the official cash rate or the lender's variable rate during that time. The lender funds your fixed loan by borrowing at wholesale rates that match the term of your fixed period. If you break that contract early, they're left with a funding mismatch.

Consider a property investor who fixed $600,000 at 5.5% for three years in early 2024, when rates were still climbing. By mid-2026, variable rates had dropped to 5.0%, and the investor wanted to refinance to a lower rate. Breaking the fixed loan triggered a break cost calculation based on the difference between the original fixed rate and the lender's current wholesale cost to fund the remaining term. In this scenario, the break cost was approximately $14,000. The investor decided to wait out the remaining 12 months rather than pay the penalty.

The contract you sign at settlement includes a clause explaining that early termination may incur costs. Most borrowers skim over it. The lender isn't required to justify the calculation method at that point, and you won't see a dollar figure until you actually request a payout quote.

What Triggers Break Costs on an Investment Loan

Break costs apply when you pay off more than the allowable extra repayments during the fixed term. Most lenders allow you to make additional repayments up to $10,000 or $30,000 per year without penalty, depending on the product. Anything beyond that threshold, or any action that reduces the outstanding balance below what the lender expected, triggers the break cost.

Selling the investment property is the most common trigger. If you need to offload the property due to tenant issues, market conditions, or personal circumstances, the entire loan balance is paid out and the lender calculates what they've lost in foregone interest. Refinancing to a different lender also triggers the same result. Even switching loan products within the same lender, such as moving from interest-only to principal and interest, can result in a payout and recalculation.

Less obvious triggers include using equity from the investment property to fund another purchase. If you're splitting the loan or restructuring your debt, the lender may treat it as a partial discharge and apply break costs to the amount being released. In our experience, investors are often caught out when they try to access equity for a deposit on a second property without realising their fixed investment loan will incur a penalty.

How Lenders Calculate Break Costs

The calculation compares the interest rate you locked in against the rate the lender can earn by reinvesting your funds for the remaining fixed term. If current wholesale rates are lower than your fixed rate, you've cost them money and they charge you the difference. If rates have risen and your fixed rate is now lower than what the lender could charge a new borrower, the break cost is usually zero.

The formula itself is opaque. Lenders use the present value of the lost interest income, discounted back to today's dollars. The longer the remaining fixed term, the higher the potential cost. A break cost on a loan with six months remaining might be a few hundred dollars. A break cost with three years remaining could reach tens of thousands.

Lenders are required to provide a discharge authority or payout figure when you request it, and the break cost will be itemised on that statement. You won't see the underlying wholesale rate used in the calculation, and most lenders won't negotiate the figure. The Australian Securities and Investments Commission requires that the method be reasonable, but there's no standard formula across the industry. Each lender applies their own margin and rounding.

If you're comparing investment loan options and you think there's any chance you'll need flexibility during the fixed term, ask the broker or lender for a worked example of what a break cost might look like at different points in the loan. Some lenders publish break cost calculators, but most don't.

Split Loans and How They Reduce Exposure

A split loan divides your investment loan into two or more portions, typically one fixed and one variable. The variable portion gives you flexibility to make extra repayments, access a redraw facility, or pay off part of the loan without penalty. The fixed portion protects you from rate rises on the majority of your debt.

Splitting doesn't eliminate break costs, but it reduces the amount exposed to them. If you split $700,000 as $500,000 fixed and $200,000 variable, only the fixed portion will incur break costs if you exit early. The variable portion can be paid down or refinanced at any time. The exact split ratio depends on your risk tolerance and how much flexibility you think you'll need.

Some investors prefer a 50/50 split. Others go 70% fixed and 30% variable, leaning toward rate protection while keeping some liquidity. There's no single formula, but the decision should be informed by your holding period and whether you're planning to use equity from the property within the fixed term. A Mount Eliza investor holding a long-term investment property with stable rental income and no plans to sell might comfortably fix 80% of the loan. An investor building a portfolio and likely to refinance within two years should keep at least 40% variable.

Split loans are offered by most major lenders and are structured at no additional cost compared to a single-rate loan. You'll receive two loan accounts, each with its own repayment schedule and statement.

When Fixed Rates Make Sense for Investment Property

Fixing makes sense when you're confident you'll hold the property for the full fixed term and you want certainty over your repayments. If rental income is tight and a rate rise of 0.5% would push your cash flow into the red, a fixed rate provides a buffer. If you're relying on negative gearing to reduce your taxable income and you can't afford to lose that predictability, fixing part of the loan reduces exposure to repayment shocks.

Fixed rates also suit investors who lack the temperament for rate volatility. If every Reserve Bank announcement sends you checking your loan balance and recalculating your repayments, a fixed rate removes that mental load. The cost of certainty isn't just financial.

Variable rates suit investors who want flexibility to pay down debt quickly, access redraw, or refinance without penalty. Variable rates also allow you to take advantage of rate cuts without being locked into a higher rate. At current variable rates, the difference between a competitive variable investment loan and a three-year fixed rate might be 0.3% to 0.5%. Over three years on a $600,000 loan, that difference could amount to $10,000 in additional interest, but you're buying rate protection and repayment stability in exchange.

If you're unsure whether you'll hold the property for the full term, or if there's any chance you'll need to sell, restructure, or access equity, don't fix the full loan amount. A split structure or a shorter fixed term of one to two years reduces your exposure to break costs while still giving you some rate protection.

What to Do If You're Locked Into a Fixed Rate and Need to Exit

If you need to sell or refinance during a fixed term, request a payout quote from your lender as early as possible. The break cost is calculated on the day you request the quote and is typically valid for 10 business days. If rates move during that window, the figure may change.

Some lenders allow you to port a fixed rate loan to a new property if you're selling one investment property and buying another. Porting transfers your existing fixed rate and remaining term to the new loan, avoiding break costs entirely. Not all lenders offer this feature, and it only works if the new loan amount is similar to the old one. If you're upsizing significantly, the additional borrowing will be priced at current rates and only the ported portion retains the old fixed rate.

If the break cost is high and you're not forced to sell, consider waiting until closer to the end of the fixed term. Break costs reduce as the remaining term shortens, so a cost that's $12,000 with 18 months remaining might drop to $3,000 with six months remaining. If you're refinancing purely to chase a lower rate, run the numbers to see whether the saving over the remaining fixed term exceeds the break cost. In many cases, it doesn't.

If you're facing genuine hardship and the fixed rate is preventing you from managing the loan, contact the lender's hardship team. They may allow you to switch to interest-only repayments or extend the loan term without charging the full break cost, depending on your circumstances.

Where to Get Help With Investment Loan Structure

Choosing between fixed, variable, and split structures isn't something you should do based on a rate comparison table. Your decision depends on your cash flow, your plans for the property, your risk tolerance, and whether you're likely to need equity or flexibility during the loan term.

A mortgage broker who works with property investors regularly can model different scenarios and show you what a break cost might look like if you exit early, what your repayments would be under a split structure, and which lenders offer the most flexibility on fixed rate products. Call one of our team or book an appointment at a time that works for you.

Frequently Asked Questions