United Kingdom Mortgage Calculator
5-year fixed (75% LTV):4.98%· Sept 2026
Your loan
Pre-filled with the latest official average: 4.98% (Sept 2026, Bank of England).
- Principal & interest£1,575
- Insurance£38
Upfront costs
- Down payment£30,000
- Stamp duty£0
- Legal fees%£1,500
- Lender fees%£1,200
- Cash needed at purchase£32,700
What if interest rates change?
Your payment today is just the start. See how it could move if rates go up or down during your loan.
Range: 4.73% to 5.23% · The rate resets once a year after month 60.
Likely range of your monthly payment
- Most likely
- 80% of outcomes
- Middle 50% of outcomes
- If today's rate holds
In 8 out of 10 simulated futures, you pay between £199,292 and £206,162 in total interest (today's rate: £202,575).
| Scenario | Avg. monthly | Highest monthly | Total interest | vs. today |
|---|---|---|---|---|
| Rate stays at 4.98% | £1,575 | £1,575 | £202,575 | — |
| Drops to 4.73% at first reset | £1,549 | £1,575 | £194,733 | ▼ −£7,841 |
| Rises to 5.23% at first reset | £1,602 | £1,608 | £210,505 | ▲ +£7,930 |
| Climbs steadily to 5.23% | £1,584 | £1,593 | £205,284 | ▲ +£2,709 |
| Falls steadily to 4.73% | £1,566 | £1,575 | £199,881 | ▼ −£2,693 |
| Spikes to 5.23% for 3 years | £1,582 | £1,608 | £204,596 | ▲ +£2,021 |
Based on 600 simulated rate paths that drift randomly within your range and tend back toward today's rate. This is an illustration, not a forecast.
Loan balance over time
- Remaining balance
- Interest paid (cumulative)
- Principal paid (cumulative)
Interest rates in United Kingdom
Monthly averages. Sources: Bank of England
- 2-year fixed (75% LTV)
- 5-year fixed (75% LTV)
Buying a home in United Kingdom: rules and costs
- Most UK mortgages are fixed for 2 or 5 years, then move to the lender's standard variable rate unless you remortgage.
- Stamp Duty Land Tax (England and Northern Ireland) from April 2025: 0% up to £125,000, 2% to £250,000, 5% to £925,000, 10% to £1.5m and 12% above.
- First-time buyers pay no stamp duty up to £300,000 and 5% on the portion up to £500,000, if the price is £500,000 or less.
- Scotland (LBTT) and Wales (LTT) have their own property taxes with different bands.
- Lenders typically cap borrowing at around 4.5× household income, with 90–95% loan-to-value products available.
Sources: GOV.UK — Stamp Duty Land Tax · Bank of England database · Rules last reviewed 2026-10.
Frequently asked questions
How is the monthly mortgage payment calculated?
For an equal-payment loan, the payment is P × i × (1 + i)^n ÷ ((1 + i)^n − 1), where P is the loan amount, i the monthly interest rate and n the number of months. Taxes, insurance and fees are added on top.
What is the current average mortgage rate in United Kingdom?
The latest official figure is 4.98% for 5-year fixed (75% LTV) (Sept 2026, source: Bank of England). Your own rate depends on your deposit, income, credit history and lender.
How much does a 1-point rate rise change my payment?
On a £270,000 loan over 25 years, going from 4.98% to 5.98% raises the monthly payment from £1,575 to £1,736 — about £161 more each month.
What upfront costs should I budget for in United Kingdom?
On a £300,000 purchase, expect about £7,700 in taxes and fees on top of your down payment. The breakdown is shown in the calculator above.
Can this calculator predict future interest rates?
No. The scenario tool shows a range of possible outcomes based on the band you choose. Nobody can predict rates reliably — use it to check whether you could still afford the loan if rates rise.