MORTGAGECALCULATOR
Calculate your monthly mortgage payment including principal, interest, property tax, and home insurance.
Parameters
20.0% down
What does a mortgage calculator actually tell you?
A mortgage calculator takes three numbers — how much you're borrowing, the interest rate, and how long you're spreading the repayments — and works out what you'll pay each month. That's it. But knowing that monthly number is genuinely useful before you commit to anything. Here's the thing most people miss: the calculator shows you what the mortgage costs, not necessarily what you can afford. Those are different questions. A lender might approve you for £300,000, but if the monthly payments leave you nothing for groceries, that's not the right mortgage. Use the calculator to find a payment you're comfortable with first, then work backwards to the loan amount.
How to use this calculator
Put in the numbers you actually know, not the numbers you hope for. The result is only as useful as the inputs.
Property price and deposit
Enter the property price and how much deposit you have. The difference is your loan amount (LTV). Getting this right matters — your rate changes at key deposit thresholds like 10%, 15% and 25%.
Interest rate
Use the actual rate from a real mortgage offer or quote, not a guess. If you don't have one yet, use the current average for your LTV bracket as a starting point — but know it'll shift.
Mortgage term
How many years are you planning to repay over? Most UK mortgages run 25–35 years. A longer term reduces your monthly payment but increases total interest paid significantly.
Read the total, not just the monthly
Scroll down past the monthly figure and look at the total interest over the full term. That number is often a shock — and a useful reminder that overpaying when you can makes a real difference.
The formula lenders use
M is your monthly payment, P is the loan amount, r is the monthly interest rate (annual rate divided by 12), and n is the total number of monthly payments. So a £200,000 mortgage at 4.5% over 25 years: monthly rate = 0.045/12 = 0.00375, n = 300 payments, giving a monthly payment of £1,111. The maths is fiddly but the calculator handles all of it instantly.
Tips & Best Practices
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Run the numbers before you find a property you love — it keeps emotions out of the budget conversation
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Compare the total interest cost of a 25-year versus 30-year term, not just the monthly payment difference
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Even overpaying £100 a month on a typical UK mortgage can cut years off the term and save tens of thousands
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A mortgage broker can often access deals not available direct from lenders — worth the conversation especially for first-time buyers
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Factor in all the other costs too: stamp duty, solicitor fees, survey, buildings insurance, and any service charges
Frequently Asked Questions
Mandeep Singh · 25+ Years UK Financial Services
Important Information
This calculator is for illustrative purposes only and does not constitute mortgage advice, a personal recommendation, or a mortgage offer.
Results are based on the figures you enter and assume a standard capital repayment structure. Actual rates, fees, terms, and eligibility will vary by lender and individual circumstances.
You should seek independent advice from a qualified mortgage adviser or broker before making any financial commitment.
Mandeep Singh · 25+ Years UK Financial Services
Important Information
This calculator is for illustrative purposes only and does not constitute mortgage advice, a personal recommendation, or a mortgage offer.
Results are based on the figures you enter and assume a standard capital repayment structure. Actual rates, fees, terms, and eligibility will vary by lender and individual circumstances.
You should seek independent advice from a qualified mortgage adviser or broker before making any financial commitment.