UK Mortgage Calculator

UK repayments, worked out properly

On a £300,000 property with a 10% deposit (£30,000), the loan is £270,000. At an illustrative 4.5% fixed rate over 25 years the repayment is about £1,501 a month, and total interest over the term is roughly £180,000. Stretch to 30 years and the repayment falls to about £1,368 — but total interest climbs by roughly £42,000. Add council tax (band-dependent, ~£1,800 a year in this example) and buildings insurance to see the true monthly outgo, which is what the calculator above does.

How UK mortgage deals actually work

• Fixed deals (2 or 5 years) hold the rate steady, then you drop onto the lender's standard variable rate (SVR) — usually far higher — unless you remortgage or take a product transfer. Most UK borrowers refix repeatedly.
• Trackers follow the Bank of England base rate plus a margin, so payments move with rate decisions.
• Product fees (£0–£1,500+) can be added to the loan, but then you pay interest on the fee for decades; paying it upfront is usually cheaper.
• Early repayment charges typically allow overpaying about 10% of the balance per year during a fixed deal without penalty.

Costs beyond the repayment

Stamp Duty Land Tax applies in England and Northern Ireland (Scotland uses LBTT, Wales LTT): as of 2025 most buyers pay nothing on the first £125,000, with first-time buyer relief covering the first £300,000 on homes up to £500,000 — always confirm current thresholds on GOV.UK before budgeting. Add valuation and legal fees, and for leasehold flats, service charges and ground rent (the calculator has a field for these).

Repayment vs interest-only in the UK

Residential interest-only is restricted: lenders require a credible repayment strategy (investments, sale of the property, other assets) and typically larger deposits. Buy-to-let remains the main interest-only market. For a home you live in, a repayment structure — modeled here — is the default for good reason. US readers: our main mortgage payment calculator covers dollars, US taxes and PMI.