Mortgage Stress Test Calculator

This calculator checks whether you could still afford your mortgage repayments if interest rates rose, the same stress test lenders apply before approving a loan. You enter your loan amount, the loan term in years, your current interest rate, and a higher test rate you want to check yourself against. The calculator works out your principal and interest repayment at both rates over the remaining term and returns your current repayment, your stressed repayment at the test rate, the extra amount you would pay each month, and what that adds up to over a year. Because banks typically test loans against a rate a few percentage points above the one you are actually paying, running the same check yourself shows whether you have a genuine buffer or are borrowing right to your limit. It is useful whether you are a buyer working out how much you can safely borrow, or an existing homeowner wanting to see how much your repayments could rise at the next refix. Try raising the test rate to see how sensitive your budget really is to another round of rate rises. Repayments are calculated on a standard table (principal and interest) basis, and the results are an indicative estimate only, not financial advice, so check your own numbers with your lender before making borrowing decisions.

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Repayments are calculated on a table (principal and interest) basis over the remaining term. A test rate a few percentage points above your current rate is a sensible resilience check. Make sure your budget could absorb the extra before borrowing to your limit. Estimate only, not financial advice.