Mortgage Calculator
Calculate your exact monthly mortgage payment and total cost over the full term. See how much goes to interest vs capital, and how overpayments could save you thousands.
Mortgage Guide
Repayment vs Interest Only
A repayment mortgage reduces your loan balance every month — by the end of the term, you own the property outright. An interest-only mortgage keeps payments lower but you still owe the full loan at the end and need a separate plan to repay it. Interest-only mortgages are now rare for residential buyers and typically reserved for buy-to-let investors.
Why Your LTV Ratio Matters
LTV (Loan to Value) = mortgage amount ÷ property value × 100. The lower your LTV, the better the mortgage rate you can access. Key thresholds: 95% (minimum deposit most lenders accept), 90%, 85%, 80%, 75%, and 60%. Crossing below 75% and especially 60% LTV typically unlocks the best rates. Each 5% improvement in LTV can save 0.2–0.5% on your interest rate — worth calculating over a 25-year term.
The Power of Overpayments
Most UK mortgage products allow overpayments of up to 10% of the outstanding balance per year without penalty. Even £100/month extra on a £270,000 mortgage at 4.5% over 25 years saves approximately £18,000 in interest and shortens the term by 2–3 years. The earlier in the mortgage term you overpay, the greater the compounding benefit.
Fixed vs Variable Rates
Fixed rate: your payment stays the same regardless of Bank of England base rate changes — ideal for budgeting certainty. Tracker: moves with the base rate — lower when rates fall, higher when they rise. Discount: a set amount below the lender's standard variable rate (SVR). Most buyers choose a 2–5 year fixed rate then remortgage when the deal expires.
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