Mortgage refinance calculator: savings, costs and risks

Natloans provides a mortgage refinance calculator to help you estimate how a change in loan balance, interest rate, or loan term might affect your repayments and total interest costs. The calculator is designed to give you a starting point for comparing your current home loan with a potential new arrangement — not a guaranteed outcome. Use it alongside a conversation with a Natloans broker to understand the full picture before making any decisions.

How to Use the Mortgage Refinance Calculator

The interactive tool is available directly on the Natloans website. To get a meaningful estimate, you will need the following information ready:

  1. Current loan balance — the remaining principal you owe on your existing mortgage.
  2. Current interest rate and monthly repayment — these establish your baseline cost.
  3. Proposed new loan details — including the interest rate, loan term, and any fees associated with the new loan.

Once entered, the calculator compares estimated monthly repayments, total interest payable, and overall loan cost between your current loan and the proposed refinance. Review the assumptions built into any estimate before relying on the result, and confirm current rates and fees directly with Natloans or the relevant lender.

Open the interactive Natloans Mortgage Refinance Calculator

Why People Refinance Their Mortgage

Refinancing means replacing your existing home loan with a new one — either with your current lender or a different one. The source page published by Natloans (last modified August 2026) identifies four common reasons borrowers consider refinancing:

Common Refinancing Goals
Goal What It May Achieve
Lower interest rate Reduced repayments and potentially lower total interest over the life of the loan
Shorter loan term Faster path to full ownership, though monthly repayments may be higher
Lower monthly payments Improved monthly cash flow, though a longer term may increase total interest paid
Debt consolidation Combining higher-interest debts into a single loan at a potentially lower rate

Whether any of these outcomes applies to your situation depends on your current loan terms, credit profile, and the options available to you at the time you apply. None of these are guaranteed results.

What to Consider Before Refinancing

The calculator provides an estimate based on the numbers you enter, but the true cost of refinancing includes factors that sit outside the repayment comparison. Natloans highlights three key considerations:

Break Costs and Exit Fees

Some lenders — particularly those offering fixed-rate loans — charge break costs or exit fees if you leave before the end of a fixed term. These costs can be substantial and may offset any savings from a lower rate on a new loan. Check your current loan contract or ask your lender for a break-cost estimate before proceeding.

Loan Term Impact

Extending your loan term to reduce monthly repayments can result in paying significantly more total interest over time, even if the rate is lower. The calculator allows you to compare overall loan cost — not just the monthly figure — which is important for assessing the real value of refinancing.

Your Credit Score

Lenders assess your credit profile when you apply for a refinance. A strong credit history generally supports access to more competitive rates. You can review your credit file before applying — Natloans provides a link to a credit file tool as part of its calculator and tools section.

For broader guidance on what to factor in when switching home loans, the Australian Securities and Investments Commission's MoneySmart resource on switching home loans is a useful independent reference: moneysmart.gov.au — Switching Home Loans.

Estimating Your Refinancing Savings Accurately

A repayment comparison alone does not capture the full cost of refinancing. To estimate savings accurately, account for all of the following:

  • Exit costs or break fees on your existing loan
  • Application, valuation, and legal fees on the new loan
  • Ongoing fees (annual fees, redraw fees, offset account fees) associated with the new loan
  • The impact of any change in loan term on total interest paid

Comparing the overall loan cost — not just the monthly repayment — gives a more complete picture of whether refinancing makes financial sense in your circumstances. Confirm all fees and current rates with Natloans or the relevant lender before making a decision.

Checking Your Eligibility Across Lenders

Natloans offers an online eligibility check across a panel of lenders. The source page indicates access to over 50 lenders, though this figure should be confirmed with Natloans as lender panels can change. Checking eligibility online does not constitute a formal loan approval; it is a preliminary step to understand which products and lenders may be available to you.

Check your eligibility or apply for a home loan with Natloans

Helpful Resources

Frequently Asked Questions

What should I include when estimating refinancing savings?

Allow for your existing loan's exit costs and any break costs, the new loan's setup and ongoing fees, and the effect of any change in loan term. Compare the overall cost of each loan — not just the monthly repayment — to get a realistic picture. The MoneySmart guide on switching home loans (moneysmart.gov.au) provides a useful independent framework. Source: Natloans Mortgage Refinance Calculator page.

Where can I use the interactive mortgage refinance tool?

The interactive tool is available on the original Natloans calculator page. This page preserves readable information about how refinancing works and what to consider, but you need to use the original tool for interactive inputs and results. Always check the assumptions the calculator uses before relying on an estimate. Source: Natloans Mortgage Refinance Calculator.

Does using the calculator commit me to anything?

No. The calculator is an estimation tool only. Using it does not constitute a loan application or a commitment by Natloans or any lender. Any formal application is a separate step.

Can I use the calculator for debt consolidation scenarios?

Debt consolidation is listed as one of the reasons people refinance. You can input the proposed new loan details — including a balance that reflects consolidated debt — to compare estimated repayments and total cost. Whether debt consolidation refinancing is suitable for your situation is a question to discuss with a Natloans broker, as it depends on the types of debt, interest rates, and your overall financial position.

What is a comparison rate and why does it matter?

A comparison rate includes interest and specified fees for an example amount and term; it does not include every possible cost or establish your actual cost. The captured calculator page contains blank rate placeholders, not a usable current rate offer. Obtain a current quote and check all switching costs.

How does my credit score affect a refinance application?

Lenders review your credit profile as part of any home loan application, including a refinance. A stronger credit history generally supports access to more competitive rates and a broader range of lenders. You can access your credit file through the tool linked in Natloans' resources section before applying.

Will extending my loan term always reduce my repayments?

Extending the loan term typically lowers the monthly repayment amount, but it also means paying interest for a longer period, which can increase the total amount paid over the life of the loan. The calculator is designed to help you see this trade-off by comparing both monthly repayments and overall loan cost.

What are break costs and when do they apply?

Break costs are fees some lenders charge when a borrower exits a fixed-rate loan before the end of the fixed term. They can be significant depending on the remaining fixed period and prevailing interest rates. Check your current loan contract or contact your lender for a specific break-cost figure before proceeding with a refinance.

Do I need to refinance with a new lender, or can I refinance with my current lender?

Refinancing can occur with your existing lender (sometimes called a loan variation or internal refinance) or with a new lender. Both options have different cost and process implications. A Natloans broker can help you compare options across the lender panel.

How do I take the next step after using the calculator?

If the calculator estimate suggests refinancing may be worthwhile, the next step is to check your eligibility and speak with a Natloans broker. You can begin that process through the Apply for a Home Loan page or the Refinance My Home Loan page.

Next Steps

  1. Use the calculator — enter your current loan details and proposed new loan details to see an estimated comparison. Open the calculator.
  2. Review your credit file — understand your credit position before applying. Get your credit file.
  3. Check your eligibility — use the Natloans online eligibility check to see which lenders and products may be available to you. Check eligibility.
  4. Speak with a broker — discuss your specific situation, including exit costs on your current loan, to determine whether refinancing makes sense. Explore refinancing options.

Sources and References

  • Natloans Mortgage Refinance Calculator page — natloans.com.au. Published 13 June 2025; last modified 5 August 2026 (as retrieved 15 October 2026). Rates, lender counts and fees must be confirmed with Natloans as current.
  • MoneySmart — Switching Home Loans — moneysmart.gov.au. Published by ASIC. Independent guidance; confirm currency at time of use.

Debt consolidation and repayment risk

If unsecured debts are added to a mortgage, the home may become security for those debts. A lower rate or monthly payment can still mean a higher total cost if repayment is stretched over a longer period. Keep the existing remaining term in view, include all fees, and ask how any consolidated debt can be repaid without simply extending it for decades. See ASIC Moneysmart’s debt consolidation guidance.

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