Bridging Loan Calculator NZ
This calculator estimates the interest cost of bridging finance, the short-term loan that lets you buy your next home before your current one has sold. Bridging finance covers the overlap between settlement on your new property and the sale of your existing one, and because it is short-term and higher-risk for the lender, it usually carries a steeper interest rate than a standard mortgage. You enter the amount you expect to bridge, the interest rate charged, and how many weeks you expect the overlap to last. The calculator then works out the total interest cost over that period, the equivalent cost per week so you can see how quickly the bill grows, and what you would owe if your sale took twice as long as planned, since a slow sale is the biggest driver of blown-out bridging costs. Use it to weigh up whether bridging finance is affordable for your situation, and to see how much a delay in selling could cost you before you commit. Because settlement dates slip more often than sellers expect, it pays to budget for a longer overlap than you hope for, and to check whether your lender charges any establishment or account fees on top of the interest shown here. This is an indicative estimate only, not financial advice, and your bank's actual rate and terms may differ.
The main risk is your current home taking longer to sell than expected, which extends the interest. Plan for a longer overlap than you hope for, and check any fees on top of interest. Estimate only, not financial advice.
How it works
The calculator works out the interest on the bridged amount over the overlap period, as the amount times the annual rate, scaled to the weeks of overlap. It shows the weekly cost so you can see how each extra week of delay adds up, and a scenario where the sale takes twice as long, since a slow sale is the main way bridging costs blow out.
Worked example
Bridging $500,000 at 8% for 12 weeks costs about $9,230 in interest, or roughly $769 a week. If the sale took 24 weeks instead, the cost would roughly double to about $18,460, showing why a quick, well-priced sale of your current home matters.
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