Revolving Credit Calculator

This calculator shows how much interest you can save by using a revolving credit facility instead of a standard mortgage, by parking your income and savings against the loan balance rather than in a separate account. A revolving credit facility works like a large, interest-only overdraft secured against your home: your everyday income sits in it, offsetting the balance interest is charged on, and you draw on it as needed for spending and bills. You enter your revolving credit balance, the interest rate, and the average amount of funds you expect to keep parked in the facility day to day. The calculator works out the interest you would pay on the full balance, the reduced interest once your average parked funds are counted, and the estimated interest saved per year. It is a useful way to see whether the flexibility of revolving credit is worth it, and how much discipline matters: the saving only holds if you consistently keep funds parked rather than spending down the facility, since the credit is always available to draw on. Use it alongside your mortgage statements to test different balances, rates and parked-fund scenarios before choosing a facility structure. This is an indicative estimate only, not financial advice, and your real saving depends on how your bank calculates interest and how disciplined you are with the account.

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Interest is charged on the balance after the funds you keep in the facility. The saving depends on how much you keep parked and for how long, so discipline is key; the credit is always available to spend. Estimate only, not financial advice.