Mortgage calculator

By The PocketSums team. Updated 30 September 2026. How we calculate

Enter the price, your deposit, the rate and the term to see your monthly payment and the total interest over the life of the mortgage.

£200,000 at 4.5%, 25 years
£1,112 a month
Same loan over 35 years
£947 a month
Each 1% on the rate adds
about £117
Typical income multiple
4 to 4.5 times
Stamp duty calculatorHow much can I borrow?
  • HMRC 2026/27 rates
  • Private: nothing leaves your device
  • Free, no sign-up

Monthly payment£1,500.75a month

Borrowing £270,000 (90% loan to value). Total repaid £450,225, of which £180,225 is interest.

Monthly repayments by loan and rate (25 years)

Loan 3.5% 4% 4.5% 5% 5.5%
£100,000 £501 £528 £556 £585 £614
£150,000 £751 £792 £834 £877 £921
£200,000 £1,001 £1,056 £1,112 £1,169 £1,228
£250,000 £1,252 £1,320 £1,390 £1,461 £1,535
£300,000 £1,502 £1,584 £1,668 £1,754 £1,842
£400,000 £2,002 £2,111 £2,223 £2,338 £2,456

How a £270,000 mortgage is paid off

£0k£50k£100k£150k£200k£250k£300k0y5y10y15y20y25y
  • Balance still owed
  • Total interest paid so far
A 25 year repayment mortgage at 4.5%. In the early years most of each payment is interest, so the balance falls slowly at first.

What each salary could borrow

Most lenders start at about 4.5 times income. Here is what that buys, and the monthly cost at 4.5% over 25 years.

  1. £30,000£135,000, £750 a month
  2. £40,000£180,000, £1,001 a month
  3. £50,000£225,000, £1,251 a month
  4. £60,000£270,000, £1,501 a month
  5. £75,000£337,500, £1,876 a month
  6. £100,000£450,000, £2,501 a month
A row of Victorian terraced houses

How much can you borrow?

Income multiples, deposits and affordability stress tests all decide your limit. Our guide works through it at six salaries.

How much can I borrow for a mortgage?

Buying in England or Northern Ireland? Add the tax with the stamp duty calculator, and check what you can afford each month with the take-home pay calculator.

Questions people ask

How is a monthly mortgage payment worked out?

For a repayment mortgage each payment covers that month's interest plus some of the loan, so the payment stays the same while the balance falls. The formula is P x r / (1 - (1 + r)-n), where P is the loan, r the monthly rate and n the number of months.

What is loan to value?

The loan as a share of the property price. A £270,000 mortgage on a £300,000 home is 90% loan to value. Lenders usually offer lower rates at 75% and 60% loan to value.

Does a longer term make a mortgage cheaper?

It lowers the monthly payment but raises the total interest you pay. On £200,000 at 4.5%, a 35 year term costs about £165 a month less than 25 years but adds tens of thousands in interest.