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Financial calculator

Mortgage Calculator UK

Estimate repayment and interest-only mortgage payments, LTV and deposit share for a UK-style mortgage.

This estimates payment only. Stamp duty, product fees, valuation fees and affordability tests are not included.

Method

The calculator subtracts deposit from property price, then estimates repayment payment with fixed-rate amortization and interest-only payment from monthly interest.

Example

For a GBP 350,000 property with a GBP 50,000 deposit, the mortgage is GBP 300,000 and LTV is about 85.7%. At 5.25% over 25 years, the repayment estimate is about GBP 1,797 per month.

Common mistakes

Do not ignore product fees, stamp duty, valuation fees or remortgage changes after the initial deal period. Lenders also apply affordability checks.

Limitations

This is not an affordability assessment or mortgage offer. UK lenders apply income, expenditure, credit, product-fee and stress-rate criteria that are not modeled here.

References

Last reviewed: 2026-05-16

Before relying on this result

Use this calculator together with the formula, assumptions, limitations and examples on the page. If the topic involves health, tax, lending, investment, legal, safety or current-rate decisions, treat the number as an estimate and check the relevant primary source or professional guidance.

Calculator metadata last reviewed: 2026-05-14.