Calculate monthly mortgage payments, total interest, and full repayment cost.
Enter the property price and deposit
Use the agreed sale price (or your target purchase price) and the cash deposit you can put down. The difference becomes the mortgage amount.
Choose a mortgage term
Most UK terms run 25-30 years. A shorter term cuts total interest but raises the monthly payment.
Pick a representative interest rate
Use a current best-buy rate for your loan-to-value band — typically 4.5-5% in 2025/26 for 75-90% LTV.
Toggle repayment vs interest-only
Repayment clears the loan by the end of the term. Interest-only keeps the balance flat and is mostly limited to BTL or high-net-worth borrowers.
Compare total interest and monthly cost
Look at both monthly affordability and lifetime interest. A 30-year term is cheaper per month but costs significantly more over the life of the loan.
Stress-test at a higher rate
Re-run the figures at 7-8% to mimic the lender's SVR. Make sure you could still afford payments when the fixed deal ends.
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Disclaimer: All results are estimates for guidance only and do not constitute financial, tax or legal advice. Always consult a qualified professional.