Split Loan Calculator
Calculate repayments on a fixed/variable split home loan. Test rate-shock scenarios and compare to all-fixed or all-variable.
Disclaimer
This calculator provides estimates for general information purposes only. Results should not be relied upon as professional financial, tax, or legal advice. Tax rates and thresholds are based on publicly available ATO data and may change. Always consult a qualified tax agent or financial adviser for advice specific to your circumstances.
Frequently Asked Questions
What's a typical split ratio?
What are the main pros and cons?
Can I have an offset on the fixed portion?
What happens when the fixed period ends?
What is Split Loan?
Calculator for a home loan split between fixed-rate and variable-rate portions. Shows the blended monthly repayment, compares to all-fixed and all-variable scenarios, and stress-tests what happens to the variable portion if rates rise.
How this calculator works
Enter your total loan amount, fixed/variable split percentage, both rates, term in years, and a rate-shock amount. The calculator computes monthly repayments on each portion using the standard PMT formula, sums them for your split repayment, and runs three comparisons: all-fixed, the split, and all-variable. Then it re-runs the variable portion with the rate shock applied to show how much your monthly payment would rise.
Why Split a Loan?
A split loan combines the certainty of a fixed-rate loan with the flexibility of a variable-rate loan. Fixed portion: you know exactly what your repayment will be for 1–5 years, protected from rate rises. Variable portion: you keep access to offset accounts, unlimited extra repayments, redraw, and rate cuts when they happen. The split protects you partially from both rate rises (fixed) AND from being locked in if rates fall (variable).
Common Split Ratios
60% fixed / 40% variable is the most popular configuration in Australia, especially during rate-cycle uncertainty. 50/50 is a true hedge — you're indifferent to rate direction. 70/30 favours stability (low risk tolerance); 30/70 favours flexibility (you want to make extra repayments). Choose your split based on: (1) how much spare cash you want sitting in offset, (2) your view on rates, and (3) your risk tolerance.
Offset Accounts on Split Loans
Most banks only allow 100% offset on the VARIABLE portion of a split loan. That's a key reason to keep enough loan on the variable side to hold your offset balance — typically 6–12 months of expenses. Some banks (Macquarie, CommBank with the Wealth Package) offer 'partial offset' on fixed loans, but at reduced effectiveness (e.g. 40%) — full 100% offset is variable-only at most banks.
Break Costs on Fixed Portions
If you sell the property, refinance, or repay the fixed portion early during the fixed term, the bank charges 'break costs' to compensate for the interest they would have earned. These can be tens of thousands of dollars if rates have fallen since you fixed. Banks calculate break costs based on the difference between your fixed rate and the current swap rate × remaining principal × remaining time — there's no cap.
What Happens at Roll-off
When the fixed period ends, the fixed portion automatically rolls onto the bank's standard variable rate (often higher than what new customers get). At that point you have three choices: (1) re-fix at current rates, (2) leave it on variable, or (3) refinance the entire loan elsewhere. Set a reminder 60 days before the fixed period ends to negotiate proactively — banks rarely volunteer the best rate.
Updated for the 2025-26 financial year (1 July 2025 to 30 June 2026).
Official Sources
All calculations are performed in your browser — your data never leaves your device. Results are for general guidance only and should not be considered professional financial advice.
Built and maintained by Konstantin Iakovlev. Data sourced from the ATO and official Australian government sources.