UK mortgage calculator
UK mortgage repayments, interest-only costs, overpayments and Stamp Duty.
About this calculator
This UK mortgage calculator works out your monthly payment for a repayment or interest-only mortgage, from the price, deposit, rate and term.
It shows how overpayments shorten the mortgage, your loan-to-value and loan-to-income, and the Stamp Duty due in England and Northern Ireland.
How it works
A repayment mortgage pays interest and part of the loan each month with the standard level-payment formula, so it is cleared by the end of the term. Interest only pays just the monthly interest, loan × rate ÷ 12, and the whole loan is still owed at the end.
Last reviewed:
Worked example
- Property price: $300,000
- Deposit: $30,000
- Interest rate: 4.5% a year
- Mortgage term: 25 years
- Mortgage type: Repayment
- Stamp Duty: you are: A first-time buyer
Monthly payment: $1,500.75
Common questions
How much can I borrow for a mortgage in the UK?
Most lenders lend up to about 4 to 4.5 times your household income, depending on your outgoings, credit record and deposit.
How much Stamp Duty will I pay?
In England and Northern Ireland, first-time buyers pay nothing up to £300,000 and 5% on the part up to £500,000. Others pay from 2% above £125,000, and buyers of an additional home pay 5% more.
Do overpayments save money?
Yes. Extra payments come straight off the loan, so you pay less interest and finish sooner. Many fixed-rate deals allow overpayments of up to 10% a year without a fee.
Sources and further reading
The story behind it
Where the idea came from: Stamp Duty is one of Britain's oldest taxes, first introduced in 1694 to help pay for a war with France.
Since 2003 it has been Stamp Duty Land Tax on property in England and Northern Ireland. Scotland and Wales now set their own versions, with different bands.
Why you can trust this calculator
- It runs in your browser. Nothing you type into it is sent anywhere.
- The method is explained on this page, so you can check it yourself.
- Free to use, with no sign-up.
- Results are estimates, not financial advice.
- Spotted a mistake? Tell us and we'll look into it.
After 15 years as a mathematics educator, I built CalculStore to give students, teachers, professionals and anyone working with numbers simple, reliable tools.
Meet the founder