Mortgage Repayment Calculator
Your monthly payment, total interest and true total cost — for any loan size, rate and term.
Capital repayment basis with monthly compounding. Excludes product fees, insurance and rate changes after any fixed period ends.
Term length is the hidden cost lever
Stretching a £250,000 loan from 25 to 35 years cuts the monthly payment by hundreds of pounds — but can add £70,000+ of extra interest over the life of the loan. If you can afford more each month, overpaying has the same effect as shortening the term: see exactly how much interest you'd save with our Mortgage Overpayment Calculator, and check what lenders will offer you with the Mortgage Affordability Calculator.
Buying a property?
Don't forget the tax: our Stamp Duty Calculator gives your exact SDLT bill including first-time buyer relief, and if you're weighing up whether to buy at all, the Rent vs Buy Calculator finds the breakeven point.
Frequently asked questions
Using the standard amortisation formula: the monthly rate is the annual rate ÷ 12, and the payment is set so the loan reaches exactly zero at the end of the term — early payments are mostly interest, later ones mostly capital.
On £250,000 over 25 years, each 0.5% rate rise adds roughly £70 a month. That's why remortgaging at the end of a fixed period rather than lapsing onto the standard variable rate matters so much.
Longer terms lower the monthly payment but cost far more in total interest. A common strategy is taking a longer term for flexibility, then overpaying — most lenders allow 10% a year penalty-free.
No — this models the loan itself. Product fees, valuation, legal costs and SDLT are on top; use our Stamp Duty Calculator for the tax.