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All toolsMortgage calculator

Mortgage calculator

What a mortgage costs each month, on repayment and on interest only, from the loan amount, annual rate, term and product fee.

Your figuresDeterministic calculation
Interest rate4.50%
0.1%12%
Term25 years
1 year40 years
Product fee1.00%
0%5%

The figures move as you drag. The product fee is treated as added to the loan, so it is borrowed and carries interest for the whole term; pay it up front instead and set it to 0%. Nothing here is a quotation: no early-repayment charge, offset balance or lender rule is included, and no product is recommended.

Monthly, on repayment£1,684.17Capital and interest. The debt is cleared at the end of the term.
Monthly, interest only£1,136.25Interest alone. The full amount borrowed is still owed at the end.
Product fee added to the loan
£3,000
Total amount borrowed
£303,000
Interest over the term, on repayment
£202,252
Total paid, on repayment
£505,252
Interest over the term, interest only
£340,875
Capital still owed at the end, interest only
£303,000

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Plan your UK mortgage repayments

Estimate the monthly cost of a mortgage before deciding on a purchase budget. This calculator shows repayment and interest-only payments side by side, using your loan amount, annual interest rate, term and product-fee percentage.

How the tool works

  1. Enter the mortgage amount after deducting your deposit from the purchase price.
  2. Use a quoted or assumed annual rate and term. Set the product-fee percentage; the tool adds it to the loan. Set it to zero if paid upfront.
  3. Adjust the rate and term to compare payments. Submit the form to calculate even without JavaScript.

When to use it

Use it before viewing homes, comparing borrowing scenarios or discussing a remortgage. Test a higher rate as well as your starting assumption and leave room for insurance, maintenance and other household bills.

UK coverage and assumptions

The rate is held constant for the calculation. The starting figures are examples, not current mortgage deals. Lenders assess income, commitments, credit history and the property separately; this tool does not decide how much you can borrow.

Frequently asked questions

Should I enter the house price or the mortgage amount?

Enter the amount you intend to borrow. If part of the purchase is paid from your deposit, deduct that from the price first. The separate product-fee percentage is added to the amount borrowed automatically. Set it to zero if the fee is paid upfront or already included in your loan input.

What is the difference between repayment and interest-only?

A repayment mortgage pays down capital as well as interest over the term. Interest-only payments cover interest and leave the original capital to be repaid separately; you need a suitable repayment plan.

Does a longer term make the mortgage cheaper?

A longer repayment term usually reduces the monthly payment at the same rate, but normally increases total interest. Compare both the monthly commitment and the length of time you will be repaying.

Is the result a mortgage offer?

No. It is arithmetic on your inputs. Product fees, changing rates, lender rounding and your eligibility can make a real mortgage different. Use the lender’s illustration to assess an actual offer.