Top Tips to Optimise Your Investment Loan Portfolio

Your Loan Structure Decides Your Return

The structure you choose when you set up or refinance an investment loan directly affects how much equity you can extract, how much tax you can claim, and how quickly you can move on your next purchase. A fixed rate might lock in certainty, but it can also lock you out of early repayments or limit offset access. An interest-only term preserves cash flow but eventually forces a switch to principal and interest. The loan product itself shapes your portfolio growth strategy.

Consider an investor in Hexham who purchased a unit near the wetlands with a standard principal and interest variable rate loan in 2023. By mid-2026, property values in the broader Hunter region had risen, creating usable equity. But the loan structure meant every repayment reduced the debt and increased the non-deductible portion of future refinancing. Switching to interest-only and using an offset account preserved the full deductible loan balance, freed up monthly cash flow of around $400, and allowed that investor to service a second purchase without selling down.

If you hold property in an area with strong rental demand, like Hexham's industrial precinct or the residential streets near Hexham Bowling Club, your loan should reflect that stability. Variable rates with offset accounts give you flexibility to park surplus income without reducing your deductible debt. Interest-only terms extend your ability to hold and accumulate. Splitting your loan between fixed and variable lets you hedge against rate rises while keeping partial access to offset and extra repayments.

Should You Fix Part of Your Investment Loan?

Fixing a portion of your investment loan reduces exposure to rate rises without removing all flexibility. A 50-50 split between fixed and variable is common, but the right allocation depends on your cash flow buffer, your plans for the property, and whether you expect to refinance or sell within the fixed term. Fixed portions typically do not allow offset accounts or penalty-free extra repayments, and break costs apply if you exit early.

An investor holding two properties in the Hunter, one in Hexham and one in nearby Thornton, recently locked in a three-year fixed rate on half of each loan after variable rates rose sharply in late 2025. The fixed portions provided certainty on around 60 per cent of total repayments, while the variable portions retained offset access for rental income and allowed extra repayments when cash flow improved. When the Thornton property was sold 18 months later, break costs on the fixed portion came to just under $3,000, but the sale still proceeded because the capital gain and equity release outweighed the penalty.

If you are considering a split structure, run the numbers on potential break costs before committing. Lenders calculate break costs differently, and some charge based on the remaining fixed term while others base it on the difference between your fixed rate and current wholesale rates. Your broker can model scenarios across multiple lenders to identify which fixed product, if any, aligns with your plans. For more detail on how break costs are calculated and when they apply, read our guide on fixed rate expiry.

Offset Accounts Preserve Deductible Debt

An offset account linked to your investment loan reduces the interest you pay without reducing the loan balance. Every dollar in the offset is deducted from the outstanding loan amount before interest is calculated, so you pay less interest while maintaining the full deductible loan balance. For investors, this matters because any principal reduction on an investment loan reduces the amount of interest you can claim as a deduction in future years.

If you receive rental income, deposit it into your offset account rather than making extra repayments. The interest saving is identical, but the loan balance stays intact. If you later refinance to access equity for a second purchase, the full original loan remains deductible against rental income. Without an offset, every extra repayment you make reduces your deductible debt and increases the non-deductible portion of any future top-up.

Not all investment loan products include an offset account. Some lenders charge a higher rate for offset functionality, while others offer it only on variable loans or principal and interest structures. If your current loan does not include an offset and you have surplus cash flow, refinancing to a product with offset access may deliver a better tax outcome over the medium term. For a full review of your current loan structure, consider a loan health check.

Interest-Only Terms Extend Your Cash Flow Window

Interest-only repayments on an investment loan are typically lower than principal and interest repayments by 30 to 40 per cent, depending on the loan amount and rate. This frees up cash flow that can be redirected into acquiring additional property, funding renovations, or building a buffer in an offset account. Interest-only terms are usually approved for up to five years on standard loans, after which the loan reverts to principal and interest unless you apply to extend the interest-only period.

The trade-off is that you do not reduce the loan balance during the interest-only period, so your equity growth depends entirely on capital appreciation and any loan-to-value ratio improvement that comes with it. If property values stagnate or fall, your LVR may drift upward, reducing your borrowing capacity for future purchases. However, if you are holding property in an area with strong long-term growth and solid rental yield, such as Hexham's proximity to the Port of Newcastle and industrial employment, interest-only can be the right call.

From a tax perspective, the choice between interest-only and principal and interest does not change your deduction. You can only claim interest, not principal, so paying down the loan does not increase your claimable expenses. If your goal is to build a portfolio rather than pay off individual properties, interest-only keeps more capital in your hands. When the interest-only term ends, you can refinance to another interest-only term, switch to principal and interest, or sell and reinvest depending on market conditions at the time.

Leveraging Equity Without Triggering Lenders Mortgage Insurance

Equity in your existing property can be used as a deposit for your next purchase without selling or using cash savings. Lenders will typically allow you to borrow up to 80 per cent of the property's current value without requiring LMI. If your property has increased in value since purchase, the usable equity is the difference between 80 per cent of the current value and your remaining loan balance.

Hexham's median unit values have risen over the past three years, driven by affordability relative to Newcastle's eastern suburbs and demand from buyers working in nearby Beresfield, Tomago and the port precinct. An investor who purchased a two-bedroom unit for $320,000 in early 2023 with a 10 per cent deposit and an LVR of 90 per cent would have paid LMI on that purchase. If that property is now valued at $370,000 and the loan balance has reduced to $280,000, the investor has access to around $16,000 in usable equity without triggering LMI on a refinance, calculated as 80 per cent of $370,000 minus the current loan balance.

If you need more than 80 per cent to fund the next deposit, you can go above that threshold, but LMI will apply to the increased borrowing. LMI premiums rise sharply above 80 per cent LVR and are calculated on the full loan amount, not just the portion above 80 per cent. In some cases, paying LMI to access equity sooner results in a stronger overall return if the next property appreciates quickly, but that decision depends on your confidence in the market and your ability to service the higher loan amount. For more on how we assess borrowing capacity across multiple properties, speak to one of our brokers.

Refinancing to Access Better Loan Features

Refinancing your investment loan is not just about chasing a lower rate. The features available on your current loan, such as offset access, interest-only terms, portability, and redraw conditions, directly affect how you manage cash flow and structure future purchases. If your current loan does not offer the features you need, refinancing to a product that does can unlock better tax outcomes and faster portfolio growth.

Many investors refinance when they want to extend an interest-only term, consolidate multiple loans under a single facility, or switch from a fixed rate to a variable rate with offset. Others refinance to access equity after a valuation increase or to move to a lender with higher serviceability buffers that allow for a larger loan top-up. Refinancing does involve costs, including valuation fees, discharge fees from your current lender, and application fees with the new lender, but those costs are often outweighed by the benefit of a better loan structure.

If you refinance an investment loan, the costs associated with the refinance, including valuation and legal fees, are generally deductible over five years. Interest on any additional borrowing used to purchase or improve the investment property is also deductible. However, if you refinance and increase your loan for private purposes, such as buying a car or renovating your home, that portion of the interest is not deductible. Keeping investment and private borrowing separate is critical for tax clarity. For a detailed review of your current loan and whether refinancing makes sense, visit our refinancing page or speak to a broker.

Using Debt-to-Income Limits to Your Advantage

Since February 2026, lenders have been required to limit the portion of new investment loans issued to borrowers with a total debt-to-income ratio of six times or more. The limit applies at the lender level, not the borrower level, so if one lender has already reached its quarterly cap, another lender may still have capacity. This makes lender selection more important than it was 12 months ago.

If your total borrowing, including investment and owner-occupied debt, is sitting at or above six times your gross annual income, your application will fall into the capped pool. That does not mean you will be declined, but it does mean your broker needs to submit your application to a lender with room under the cap and a credit policy that suits your profile. Some lenders are more willing to approve high-DTI applications where the borrower has strong rental income, a history of managing multiple properties, or significant equity.

For Hexham investors, particularly those with stable employment in the industrial or logistics sectors around Mayfield, Carrington or the port, showing consistent income and low credit exposure outside of property can improve your chances of approval even at higher DTI levels. Rental income is included in serviceability calculations, but lenders typically shade it by 20 per cent to account for vacancy and maintenance costs. If you are close to the DTI threshold, paying down non-deductible debt such as car loans or credit cards before applying can shift your ratio and improve your position. For more on how lenders assess investment loan applications, contact a mortgage broker in Hexham who understands the local market.

Call one of our team or book an appointment at a time that works for you. We will review your current structure, model your equity position, and identify which lenders and loan products give you the best platform for growth.

Frequently Asked Questions