Mortgage Calculator
Our mortgage calculator works out monthly repayments and total interest for any mortgage. At 4.5% on £200,000 over 25 years, monthly repayments are approximately £1,111.
How Are Mortgage Repayments Calculated?
For a repayment mortgage: M = P x [r(1+r)n] / [(1+r)n-1] where P = loan, r = monthly rate, n = total payments.
Mortgage Repayment Calculator
Calculate your monthly mortgage repayments based on loan amount, rate and term.
Enter the loan amount (property price minus deposit), the annual interest rate, and the term in years. The calculation uses the standard amortisation formula: monthly payment equals principal times the monthly rate, divided by one minus the monthly rate to the power of negative total months. This is the formula all UK lenders use. A longer term reduces monthly payments but increases total interest significantly — compare the total interest paid at 25 versus 30 years to see the cost of the extended term. The overpayment field shows how much term and interest is saved by paying extra each month. Most lenders allow 10% of the balance per year without early repayment charges — check your specific terms.