UK · GBP · Core mortgage tools
UK Mortgage Calculator
Calculate repayment or interest-only monthly payments from the property price, deposit and actual rate.
Reference scope documented 2026-10-25. Residential tax bands are jurisdiction-specific. Rates, fees, budget buffers and lender ratios must come from current quotes or clearly labeled assumptions. Confirm legal buyer status and scheme conditions.
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Press Calculate estimate after entering your figures.
Educational estimate, not financial advice. Disclaimer · Methodology · Corrections.
How this estimate works
Principal = price − deposit + financed fees. Repayment uses the amortizing payment formula at nominal annual rate / 12. Interest only is principal × annual rate / 12, with the original principal due separately. At 0% the repayment model divides principal across months.
Assumptions and limits
- Amounts are GBP. Enter actual quotes, balances and costs. Planning settings are editable assumptions; no lender rate is fabricated.
- Monthly nominal-rate amortization; fixed-rate projection across the entered remaining repayment period. Actual daily accrual, payment dates, product fees, rate resets and lender rounding can differ.
- This is educational scenario arithmetic, not a mortgage offer, agreement in principle, tax assessment or scheme/credit approval.
References and further reading
A fixed deal period is not the repayment term
The repayment years describe how long the principal is spread over. A rate fixed for an initial deal period need not remain fixed for that entire time. This model holds the entered rate constant to make the scenario understandable. It does not know the follow-on rate, a future remortgage offer or the outcome of a product transfer. Check both periods in the lender's illustration before interpreting lifetime interest as a forecast.
Understand repayment and interest-only results
A repayment payment includes interest plus some principal. In an interest-only scenario, the regular payment covers interest while the starting balance remains to be settled. The lower monthly figure is therefore not evidence that the same debt has been repaid more cheaply. There must still be a credible way to clear the principal. Compare remaining debt as well as cash paid, especially when the planned ownership period is shorter than the mortgage term.
Keep product fees and buying costs distinct
A fee added to the loan increases the balance and can earn interest over the remaining schedule. A fee paid immediately uses cash without increasing principal. This page provides separate financed-charge and cash-fee inputs for that distinction. It does not decide which charges the lender allows to be financed. Legal fees, valuation, moving costs, leasehold charges and purchase taxes need their own confirmed budgets; a mortgage payment is not a full completion statement.
Choose the right purchase-tax jurisdiction
England and Northern Ireland, Scotland and Wales do not share one residential purchase-tax calculation. Use the dedicated jurisdiction tool when budgeting tax and confirm the transaction date and buyer category. A mortgage-rate quote does not establish first-time-buyer status, additional-property treatment or a residence test. This payment tool intentionally does not infer a tax exemption from the deposit or the fact that you have not used a mortgage before.
Compare over the period you expect to keep the deal
A meaningful remortgage comparison should include early repayment charges, known cashback obligations, product fees and the remaining balance at a shared date. A smaller monthly debit achieved by extending the repayment term can increase later interest. Use the remortgage comparison tool for a common horizon and enter actual quotes. The Bank of England policy rate is context for monetary policy, not a rate that this website can promise on your mortgage.
Worked United Kingdom example: UK Mortgage Calculator
This is a hypothetical arithmetic example in GBP, not a current lender quote, market observation or borrower record. The same calculator model produces the figures below. Its input assumptions are shown so that you can reproduce or change the scenario.
| Assumed input | Illustration value |
|---|---|
| Property price / applicable value (GBP) | 350,000 |
| Cash deposit available after closing reserves (GBP) | 87,500 |
| Actual / scenario annual nominal mortgage rate (%) | 4.48 |
| Remaining repayment years | 25 |
| Payment type | Capital and interest |
| Quoted fees added to principal (GBP) | 0 |
| Other quoted cash purchase costs (GBP) | 0 |
| Calculated measure | Result |
|---|---|
| Monthly principal & interest | £1,456.08 |
| Starting mortgage principal | £262,500.00 |
| Constant-rate projected interest | £174,324.58 |
| Principal left at end of interest-only model | £0.00 |
| Deposit plus entered cash costs | £87,500.00 |
| Principal / property value | 75% |
Amounts use unrounded intermediate arithmetic and are rounded only for display. Selecting different costs, rates, payment dates or terms changes the result; no illustration value is prefilled into your personal financial fields.
Questions about this United Kingdom mortgage estimate
Is the UK payment fixed until the final repayment date?
Only within the constant-rate mathematical scenario. A real deal may end sooner and move to another contractual rate. Enter a separate future-rate scenario or compare actual renewal quotes rather than treating this total as a guaranteed lender schedule.
Why does adding a product fee to the loan increase interest?
Financing adds the fee to the principal on which future interest is calculated. Paying the same fee in cash changes upfront cash instead. Compare both cases using the same remaining repayment period and include the cash fee only once.
Does this monthly payment include SDLT, LBTT or LTT?
No. These are transaction-specific purchase taxes with different jurisdictional rules. Use the relevant tax tool and a conveyancer-confirmed category, then add the resulting cash requirement to your separate completion budget.