Split your loan between a fixed and a variable rate, then see the blended repayment and how it shifts if the variable portion moves.
What a split loan estimates
A split loan divides your mortgage into two parts: a portion fixed for a set term, and a portion left on a variable rate. The calculator above works each part as its own principal-and-interest loan, at its own rate, over the same term, then adds them together. You get the total monthly repayment, what each portion contributes, and a weighted blended rate so you can see where the headline sits.
What drives the number
Two levers do most of the work: how much you fix, and the gap between the two rates. The fixed portion buys certainty — it does not move when the cash rate does. The variable portion keeps the flexibility most lenders only attach to variable lending: an offset account, redraw, and unlimited extra repayments. The stress field lets you push the variable rate up or down and see how much of your repayment is exposed — because only the variable part moves, a heavier fixed weighting dampens the swing. What the tool cannot price is the trade-off behind it: fixed-rate break costs if you exit early, and the features you give up by locking too much away. Those are policy questions, and they differ by lender.
Use it as a starting point
Treat the split as a structural decision, not a rate bet. The right ratio depends on how much certainty you need, how much you intend to pay down, and which lender's fixed-rate terms actually suit you. Book a strategy session and we will work the split against your real plan.
General information only — not personal financial product or credit advice. The estimate is indicative and depends on each lender's policy, current rates and your full circumstances. AeFin is an Australian Credit Representative (CR 464548) of Finsure (ACL 384704).