Mortgage Calculator UK

The mainstream minimum is 5% of the property price, but pricing improves in steps at 10%, 15%, 20% and 25% deposit. On a £300,000 home, moving from a 10% deposit to a 15% deposit cuts both the rate (by roughly 0.25 to 0.30 percentage points) and the loan itself by £15,000, together worth about £130 a month on a 25-year term. If you are close to a threshold, saving a little longer usually beats buying immediately.

Around 4.5 times income is the high-street default. Regulation limits each lender to 15% of new lending above 4.5× loan-to-income, so higher multiples exist but are rationed. In 2026 several major lenders offer 5.5× as standard for stronger profiles, and NatWest goes to 6.5× for joint applications with combined income above £150,000. Committed credit, meaning car finance, loans and credit cards, reduces the figure directly. Our affordability calculator models all of this.

In August 2026 the two are priced almost identically, at around 5.09% versus 5.12% on average, which is unusual and makes the choice about your circumstances rather than the price. Take five years if you value certainty, expect to stay put and want to avoid paying a product fee again in 24 months. Take two years if you might move, expect base rate cuts to feed through, or your LTV will improve sharply as you repay capital.

Product and arrangement fees, yes. You can pay them upfront or add them to the loan, and the calculator shows what adding them really costs across the term. Stamp duty is a separate one-off tax rather than a monthly cost, so it lives in the stamp duty calculator, which covers SDLT, Scotland’s LBTT and Wales’s LTT.

Compare your mortgage rate against the after-tax return on savings. At a 5.09% mortgage rate, an overpayment is a guaranteed 5.09% tax-free return, and a basic-rate taxpayer would need over 6.3% gross on savings to match it. Keep an emergency fund first, check your annual overpayment allowance (usually 10% of the balance without an early repayment charge), and then overpay. The overpayment calculator shows the years and pounds saved.

Longer terms lower the monthly payment and raise the lifetime interest sharply. On £255,000 at 5.09%: 25 years costs about £1,504 a month and £196,200 in interest; 35 years drops the payment to about £1,302 but pushes interest past £291,600. A common approach is to take the longer term for payment safety and then overpay, which gives you flexibility without locking in the higher lifetime cost.

The base rate is 3.75%, held at the Monetary Policy Committee meeting on 30 July 2026. The next decision is due on 17 September 2026. Base rate directly moves tracker and standard variable rates; fixed rates are priced off swap markets and therefore move ahead of, not with, base rate decisions.

No. This is an information tool, not advice and not a quote. Lenders assess income, credit history, committed spending and the property itself before offering anything. Use these figures to plan and compare, then speak to a whole-of-market broker or lender for a decision in principle.