UK Mortgage Calculator
UK Mortgage Calculator
Estimate monthly payments, total interest and a breakdown. Toggle yearly or monthly schedule.
This is a simple estimate. Real mortgage offers can vary due to lender criteria, compounding method, fees and rate changes.
Show full breakdown
| Year | Payments | Interest | Principal | Ending balance |
|---|---|---|---|---|
| — | — | — | — | — |
| Month | Payment | Interest | Principal | Ending balance |
|---|---|---|---|---|
| — | — | — | — | — |
Use this mortgage calculator to estimate your monthly mortgage payment, total interest and overall mortgage cost. It’s designed for quick planning and comparisons — perfect if you’re checking affordability, comparing rates, or seeing how overpayments can reduce the term and interest.
What this calculator can help with
- Estimate monthly repayments for a repayment mortgage
- Estimate payments for an interest-only mortgage
- See how a deposit changes the loan amount and LTV
- Add a product fee (paid upfront or added to the loan)
- Test a monthly overpayment and see the impact on payoff time
- View a yearly or monthly breakdown of balance, interest and principal
Good to know
- This is an estimate using a fixed interest rate for the full term.
- Real mortgages can change due to fixed-rate periods ending, lender fees and criteria.
- Overpayments may be limited by your lender (especially during a fixed-rate deal).
- Some lenders calculate interest daily; others use slightly different methods.
How to use the mortgage calculator
- Enter the property price (the purchase price).
- Add your deposit to calculate how much you need to borrow.
- Set the interest rate (APR) shown on the mortgage illustration.
- Choose your term (for example 25 or 30 years).
- Pick mortgage type: repayment or interest-only.
- Add fees and overpayments if you want to test different scenarios.
- Toggle yearly/monthly to see a full breakdown.
Mortgage repayments explained
With a repayment mortgage, each monthly payment includes both interest and principal. Over time, the interest portion usually reduces and the principal portion increases, because you’re paying down the balance.
With an interest-only mortgage, the payment mainly covers interest, and the loan balance typically stays the same unless you make overpayments. Interest-only mortgages usually require a separate repayment plan for the balance at the end of the term.
Loan-to-value (LTV) and why it matters
LTV is the percentage of the property price you’re borrowing. For example, borrowing £180,000 on a £200,000 property is 90% LTV. In the UK, LTV can affect the interest rate you’re offered — generally, a lower LTV may unlock better rates (though this can vary).
Common LTV bands people search
- 95% LTV mortgages
- 90% LTV mortgages
- 85% LTV mortgages
- 80% LTV mortgages
- 75% LTV mortgages
- 60% LTV mortgages
Try adjusting your deposit to see how it changes your LTV and repayments.
Deposit tips
- Even small deposit increases can reduce your LTV band.
- A lower LTV can reduce monthly payments and total interest.
- Remember to budget for solicitor fees, surveys and moving costs as well.
Mortgage overpayments
Overpaying your mortgage can reduce the balance quicker, which may reduce total interest and shorten the term. This calculator lets you add a monthly overpayment and shows the updated payoff time.
Some lenders apply early repayment charges or limit overpayments during fixed-rate periods (for example, allowing up to 10% per year). Always check the terms of your mortgage deal before making large overpayments.
Product fees: add to loan or pay upfront?
Many UK mortgages come with a product fee. You can either pay it upfront or add it to the loan. Adding it increases the loan amount, which can slightly increase interest over time. Paying it upfront increases your initial cash cost but may reduce your long-term interest.
Try popular mortgage examples
People often search “mortgage calculator £200,000”, “mortgage payment on £150k”, or “how much is a £250k mortgage per month”. You can test those scenarios by entering a property price, deposit, rate and term.
Example inputs to try
- £200,000 property, £20,000 deposit, 25 years
- £250,000 property, £25,000 deposit, 30 years
- £300,000 property, £30,000 deposit, 35 years
- £180,000 property, £18,000 deposit, 25 years
Rates to compare
- Try 3.5%, 4.0%, 4.5% and 5.0%
- Compare 25 vs 30 years to see monthly vs total interest
- Test a £100–£300 monthly overpayment
Monthly breakdown vs yearly breakdown
If you want a quick overview, the yearly breakdown is perfect. If you want to see exactly how interest and balance change every month, switch to the monthly breakdown. This is useful when planning overpayments or comparing similar mortgage deals.
Frequently asked questions
How accurate is this mortgage calculator?
It’s a strong estimate for planning. Some lenders calculate interest daily and may apply fees or rounding differently. Your actual mortgage illustration is the final reference.
Does this include council tax, insurance and bills?
No — the calculator focuses on the mortgage itself. For affordability planning, remember to budget for council tax, buildings insurance, service charges (if applicable), utilities, and maintenance.
What’s the difference between interest rate and APR?
The interest rate affects your monthly payment. APR is designed to reflect the overall cost including some fees. For simple estimates, using the advertised rate is fine — but APR can be useful for comparing deals with different fees.
What happens when a fixed-rate deal ends?
Many mortgages move onto the lender’s standard variable rate (SVR) after the fixed period unless you remortgage or switch product. That can change your payment. This calculator assumes a constant rate for the full term.
Can I use this calculator for remortgaging?
Yes. Enter your remaining balance as the “property price” and set the deposit to £0 (or treat deposit as cash you’ll put in to reduce the loan). It won’t be perfect for every scenario, but it’s a handy way to compare rates and overpayments.
Does it include stamp duty?
No. Stamp Duty Land Tax (SDLT) is a separate purchase cost. If you want, I can build a UK stamp duty calculator as another page.
Embed this mortgage calculator on your website
You can embed this mortgage calculator on your own website. Use the “Add this calculator to your website” button under the tool to copy the embed code.
Note: This calculator is for general guidance and planning only. For official figures, refer to your mortgage illustration or lender.