UK Mortgage Calculator
Calculate UK mortgage monthly payments online free — LTV, interest rate, term and total cost breakdown. Nothing leaves your device — fast and private.
UK mortgage repayment & Stamp Duty
- Monthly repayment£1,520.57
- Mortgage amount needed£255,000
- Loan-to-Value (LTV)85.00%
- Stamp Duty (SDLT) estimate£5,000
- Total interest over term£201,171
Calculated in your browser — nothing you type is sent anywhere.
All mortgage amortization formulas, loan-to-value calculations, and SDLT estimates run locally inside your browser memory. Financial figures, property valuations, and salary inputs are never stored or transmitted.
Repayment, loan-to-value and stamp duty in one place
Most UK mortgage calculators give you a monthly figure and stop, which leaves out the two numbers that decide whether you can actually complete: how much cash you need on the day, and which loan-to-value band you land in. This one shows all three together.
On the default example, a £300,000 property with a £45,000 deposit at 5.2 percent over twenty-five years, you borrow £255,000 and repay £1,520.57 a month. That puts you at 85 percent loan-to-value. Stamp duty is £5,000, and with the deposit on top you need £50,000 in cash before fees. Total interest over the full term is about £201,171 — noticeably more than the amount you borrowed.
Stamp duty is charged in slices
The most common mistake is applying one percentage to the whole price. Duty works like income tax: each slice of the price is taxed at its own rate. On 300,000 pounds the first 125,000 is free, the next 125,000 is charged at 2 percent, and only the last 50,000 is charged at 5 percent.
- Standard rates: 0 to 125,000 nil, then 2, 5, 10 and 12 percent in bands above it.
- First-time buyers: nil to 300,000 and 5 percent to 500,000, with the relief lost entirely above 500,000.
- England and Northern Ireland only: Scotland and Wales use different taxes and different bands.
- Payable in cash: duty cannot be added to the loan, unlike some purchase fees.
Use the loan-to-value row before you offer
Lender rates step at 90, 85, 80 and 75 percent, so a deposit that lands just above a threshold can win a better rate than a slightly lower purchase price would. Try nudging the deposit until the loan-to-value row crosses a band, then compare the monthly figure. Rates here are your input rather than a live quote, in your browser.
How to Calculate UK Mortgage Payments and Stamp Duty
- Enter Property Price & Deposit: Input the agreed purchase price and cash deposit amount to determine your net borrowing amount and LTV percentage.
- Set Interest Rate & Term: Enter your expected fixed or variable annual interest rate and mortgage repayment period (e.g. 25 or 30 years).
- Inspect Monthly Cost & Cash Required: Review your monthly repayment figure, total interest payable, and required upfront cash (deposit plus standard SDLT).
Supported Inputs & Output Formats
| Type | Format | Details & Handling |
|---|---|---|
| Input | Property Purchase Price (£) | Agreed property purchase price in pounds sterling. |
| Input | Deposit Amount (£) | Cash deposit contribution towards the purchase. |
| Input | Interest Rate & Term | Annual mortgage interest rate percentage and repayment duration in years. |
| Output | Monthly Capital & Interest Repayment (£) | Exact monthly amortization payment clearing principal and interest over the term. |
| Output | Upfront Cash Requirement (£) | Total immediate cash needed on completion: cash deposit plus standard England & NI Stamp Duty. |
Common Practical Use Cases
- Affordability Budgeting: Assess monthly repayment affordability against household income before viewing properties.
- LTV Band Optimization: Test how increasing your cash deposit by £2,000–£5,000 can push your borrowing into a lower LTV pricing tier (e.g. 85% to 80%).
- Completion Cash Estimation: Calculate total immediate liquid cash needed on moving day, combining deposit and statutory stamp duty.
Important Limitations & Technical Boundaries
- Capital repayment only: Calculates full capital and interest amortization; does not model interest-only borrowing.
- England & NI standard SDLT: Models standard England and Northern Ireland residential stamp duty. Does not calculate Scotland LBTT, Wales LTT, first-time buyer relief, or 3% second-home surcharges.
- Illustrative only / Not financial advice: Does not represent a formal lending quote. Consult an FCA-regulated mortgage advisor before committing to purchase contracts.
Frequently Asked Questions
How is stamp duty calculated?
It is charged in progressive slices, not as one flat rate on the whole purchase price. For standard residential purchases in England and Northern Ireland, 0% applies on the first £125,000, 2% on £125,001 to £250,000, 5% on £250,001 to £925,000, 10% on £925,001 to £1.5m, and 12% above £1.5m.Is this a capital repayment or interest-only mortgage?
Capital repayment. The monthly payment clears both capital and accrued interest over your chosen loan term, amortizing the balance to zero. It does not calculate interest-only mortgages.Does this calculator cover Scotland and Wales?
No. Scotland levies Land and Buildings Transaction Tax (LBTT) and Wales charges Land Transaction Tax (LTT), both with independent tax thresholds. This calculator models standard Stamp Duty Land Tax (SDLT) for England and Northern Ireland only.Does this calculate first-time buyer relief or second-home surcharges?
No. This calculator applies standard single-property residential SDLT rates. It does not factor in first-time buyer relief, the 3% additional property surcharge, or non-UK resident surcharges.Why does loan-to-value (LTV) matter so much for UK mortgages?
UK lenders price mortgage products in distinct LTV bands, typically stepping at 90%, 85%, 80%, and 75%. Increasing your deposit to cross into a lower LTV threshold often unlocks significantly lower interest rates.Does this calculator constitute official financial advice?
No. This calculator is strictly an illustrative planning tool and does not constitute financial, mortgage, legal, or tax advice. You should consult an FCA-authorized mortgage broker or lender before making borrowing decisions.