Fixed Rates and Offset Myths in Investment Loans

A fixed rate investment loan doesn't let you attach an offset account. That changes the entire cost structure of your property, and most investors in Surry Hills find out only after they've locked in.

The difference shows up immediately. On a variable investment loan, every dollar in your offset account reduces the balance you pay interest on. On a fixed loan, that option disappears. You pay interest on the full loan amount for the entire fixed term, regardless of how much cash you hold. That matters when vacancy rates in inner Sydney sit above 2 per cent and you need somewhere to park your reserve without losing deductibility on the loan interest.

Why Fixed Investment Loans Don't Offer Offset Accounts

Lenders price fixed rates based on wholesale funding costs locked in at the time you settle. An offset account creates a variable balance, which means the lender can't hedge the exposure. The two products don't function together.

Consider an investor who fixes a $700,000 loan on a two-bedroom apartment near Crown Street. They have $40,000 in savings earmarked for a future renovation. On a variable loan with offset, that $40,000 sitting in the linked account would save them around $2,800 per year in interest at a 7 per cent rate. On the fixed loan, the same $40,000 sits in a standard savings account earning interest that's fully taxable at their marginal rate. The investment loan interest remains deductible, but the savings account interest adds to their assessable income. The net position is worse, and the flexibility to redraw against the loan without breaking the fixed term is either unavailable or comes with restrictive conditions.

When Fixing an Investment Loan Rate Still Makes Sense

You fix when you value certainty over flexibility and when you don't expect to hold surplus cash during the fixed period. Investors with high debt-to-income ratios who are close to serviceability limits often fix part of the loan to stabilise repayments, particularly if they're carrying multiple properties or if rental income is the primary offset against the debt.

In Surry Hills, where vacancy periods can stretch during softer rental cycles and body corporate fees on older walk-ups can shift without warning, locking in a portion of the loan amount can protect cashflow. A split structure - part fixed, part variable with offset - lets you quarantine risk on one portion while keeping liquidity on the other. That approach works when the fixed portion covers your minimum comfortable repayment and the variable portion absorbs fluctuations in rental income or unexpected costs.

The Actual Cost of Breaking a Fixed Investment Loan Early

Break costs are calculated on the difference between your fixed rate and the rate the lender can now earn by lending that money elsewhere for the remaining term. If rates have fallen since you fixed, you'll pay the lender for the lost margin. If rates have risen, the break cost is usually zero or minimal.

An investor who fixed $600,000 at 5.8 per cent for three years and needs to sell 18 months into the term could face a break cost between $8,000 and $15,000 if variable rates have dropped to 5.2 per cent. The lender calculates the present value of the interest shortfall over the remaining 18 months, adjusted for their cost of funds. Some lenders publish break cost estimators. Others require a formal discharge request before they'll provide a figure. You don't find out the exact number until you're already committed to selling, which makes planning around a potential sale during a fixed term difficult. Refinancing during a fixed term triggers the same calculation, so moving to another lender to access equity or improve your rate usually isn't viable until the fixed period ends.

How Principal and Interest versus Interest Only Changes the Numbers

Interest-only investment loans maximise your deductible interest and preserve cashflow, but they leave the loan balance unchanged. Principal and interest loans reduce the balance over time, which cuts into your deductible interest but builds equity faster.

Under the quarantining rules that take effect in July 2027, new investors purchasing established properties won't be able to offset rental losses against wage income. That makes interest-only loans less useful for investors who were relying on negative gearing to reduce their tax. An interest-only loan on an established property acquired after the cut-off will still generate deductible interest, but the loss can only offset other residential rental income or be carried forward. For an investor in Surry Hills earning $120,000 per year and holding one negatively geared property, the ability to claim a $12,000 annual loss against salary disappears. The same loss on a principal and interest loan is still quarantined, but at least the loan balance is falling and the property is moving closer to neutral or positive cashflow. Properties classified as eligible new builds retain access to negative gearing under the old rules, which makes the interest-only structure more attractive in that specific scenario.

Fixed Rate Investment Loans and the Serviceability Buffer

Lenders assess your ability to repay an investment loan at a rate 3 percentage points above the actual product rate. That buffer applies whether you choose variable or fixed. A fixed rate of 6.2 per cent is assessed at 9.2 per cent. If your rental income, salary and other income can't service the loan at that stressed rate, you won't be approved regardless of the actual repayment.

The buffer affects how much you can borrow, and it interacts with the debt-to-income cap introduced in February this year. Lenders can only write 20 per cent of their new investor loans at a debt-to-income ratio above 6 times gross income. If your total debt across all loans is $720,000 and your gross income is $115,000, your ratio is 6.26. Some lenders will still approve the loan within their 20 per cent allocation. Others won't. Fixing the rate doesn't change the serviceability test, but it does lock you into a repayment amount that might be higher than the prevailing variable rate if the market moves. That reduces your ability to increase borrowings later without refinancing or waiting for the fixed term to expire.

What Happens to Your Investment Loan When Rates Move

On a variable investment loan with offset, you can adjust your repayment strategy as rates change. You can pay down the loan faster when rates rise, or divert surplus funds into the offset to maintain full deductibility while preserving liquidity. On a fixed loan, your repayment is set. If variable rates fall below your fixed rate, you're locked in at the higher cost. If they rise above it, you're protected but you've lost the offset functionality that would have let you manage surplus cash efficiently.

In our experience, investors in inner Sydney often underestimate how much flexibility they'll need over a three or five year period. A tenant leaves, a strata special levy hits, or an opportunity to buy a second property appears. The inability to redraw or offset during a fixed term means those events require either an external line of credit or a sale, both of which carry their own costs and complications.

Call one of our team or book an appointment at a time that works for you. We'll walk through the current investment loan options that suit your situation and show you how the numbers actually sit across fixed, variable and split structures before you commit.

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