UK Mortgage Calculator
Estimate monthly mortgage repayments, total interest and loan-to-value for a repayment or interest-only mortgage. This is an estimate for general guidance, not a mortgage offer, affordability assessment or lending decision.
Assumes the interest rate you enter stays the same for the whole term, with no fees, overpayments, payment holidays or rate changes. Does not include arrangement fees, valuation fees, legal fees, Stamp Duty or insurance.
Your mortgage at a glance
| Figure | Value |
|---|---|
| Deposit percentage | 10% |
| Annual interest rate | 4.5% |
| Mortgage term | 25 years |
Where your mortgage payments go
Over the modelled term, your total repayment is made up of the original amount borrowed (capital) and the interest charged on it.
| Component | Amount |
|---|---|
| Capital (amount borrowed) | £270,000.00 |
| Interest | £180,224.31 |
How the Mortgage Calculator works
Enter the property price, deposit, interest rate and term, and choose repayment or interest-only. The calculator works out your mortgage amount and estimates the monthly payment using the standard capital-and-interest amortisation formula, or a straightforward interest calculation for interest-only.
This is an estimate for general guidance. It is not a mortgage offer, an affordability assessment or a lending decision, and it does not tell you how much a lender will lend you.
Repayment mortgages
With a repayment mortgage, each monthly payment covers both interest and a portion of the capital you borrowed. Assuming the interest rate and payments stay as modelled, the mortgage is fully repaid by the end of the term.
Interest-only mortgages
With an interest-only mortgage, monthly payments cover only the interest charged on the amount borrowed. The capital is not reduced during the term and remains fully outstanding at the end, so a separate plan is needed to repay it.
How mortgage interest affects repayments
Higher interest rates increase both the monthly payment and the total interest cost. Lower rates reduce them, all else being equal. This calculator assumes the interest rate you enter stays the same for the whole term; in reality, fixed-rate deals may end before the mortgage term does, and variable or tracker rates can change.
Current Bank of England Bank Rate
- Current rate
- 3.75%
- Effective from
- 18 December 2025
The Bank of England Bank Rate influences borrowing costs across the economy, but it is not a mortgage rate. Mortgage rates are set by individual lenders and vary by product, loan-to-value, term and borrower circumstances.
Official source
How mortgage term affects repayments
A longer mortgage term generally reduces the monthly repayment for the same mortgage amount and interest rate, but normally increases the total interest paid over the life of the mortgage. A shorter term generally increases monthly repayments but reduces the period over which interest accrues.
What loan-to-value means
Loan-to-value (LTV) compares your mortgage amount with the property's value, expressed as a percentage. For this calculation, your mortgage of £270,000.00 against a property price of £300,000.00 gives an LTV of 90%. This figure does not determine which mortgages you qualify for; lenders set their own LTV criteria.
Capital versus interest
Capital is the amount you originally borrowed. Interest is the cost charged by the lender for borrowing it. With a repayment mortgage, each payment gradually shifts from mostly interest towards mostly capital as the outstanding balance falls. With interest-only, every payment is interest, and the capital is repaid separately at the end.
What this calculator does not include
- Arrangement, product, valuation or broker fees
- Legal and conveyancing fees
- Stamp Duty (or the Scottish/Welsh equivalents)
- Buildings or life insurance
- Early repayment charges
- Moving costs
Worked mortgage examples
| Example | Mortgage | Rate | Term | Type | Monthly payment | Total interest |
|---|---|---|---|---|---|---|
| £250,000 property, £25,000 deposit | £225,000.00 | 4.5% | 25 years | Repayment | £1,250.62 | £150,186.92 |
| £350,000 property, £70,000 deposit | £280,000.00 | 4% | 30 years | Repayment | £1,336.76 | £201,234.62 |
| £300,000 property, £30,000 deposit | £270,000.00 | 5% | 25 years | Interest-only | £1,125.00 | £337,500.00 |
Mortgage repayments by amount
See estimated monthly repayments for one of these common mortgage amounts, using the same illustrative rate and term as above.
Frequently asked questions
How are mortgage repayments calculated?
How much would a £200,000 mortgage cost per month?
What is a repayment mortgage?
What is an interest-only mortgage?
What does loan-to-value mean?
Does a larger deposit reduce mortgage repayments?
Does a longer mortgage term reduce monthly payments?
Why does a longer mortgage term increase total interest?
Does this calculator include mortgage fees?
Does this calculator tell me how much I can borrow?
What happens if mortgage interest rates change?
Official sources
Last reviewed
Reviewed
Version 1.0.0
This calculator provides an estimate for general guidance only. It is not a mortgage offer, an affordability assessment, financial advice or a lending decision, and it does not tell you how much a lender will lend you. It does not include fees, Stamp Duty, insurance or early repayment charges. Check MoneyHelper guidance or seek professional advice if you are unsure.