Kalkulix

Mortgage calculator 2026

Enter the loan amount, interest rate and term to see your monthly payment, total interest and amortisation schedule.

Monthly payment: £1,363.53

Total paid: £490,867.20 · Total interest: £240,867.20

Amortisation schedule

YearInterestPrincipalBalance
1£12,766.05£3,596.31£246,403.69
2£12,576.79£3,785.57£242,618.12
3£12,377.56£3,984.80£238,633.32
4£12,167.86£4,194.50£234,438.82
5£11,947.10£4,415.26£230,023.56
6£11,714.74£4,647.62£225,375.94
7£11,470.13£4,892.23£220,483.71
8£11,212.69£5,149.67£215,334.04
9£10,941.66£5,420.70£209,913.34
10£10,656.37£5,705.99£204,207.35
30£446.43£15,912.33£0.00

Bank rate comparisonMarket average: 5.14 % (2026-07-10)

This calculation is indicative only. The market average is a snapshot as of the date shown and doesn't account for ERCs or individual creditworthiness. It does not replace a binding lender offer.

How a UK mortgage payment is calculated

A mortgage is repaid on a repayment (annuity) basis — the monthly payment stays the same throughout the fixed-rate period, only the split between interest and capital changes. Early on, interest makes up most of the payment; over time the balance shifts toward capital repayment.

The payment M is M = P × i / (1 − (1 + i)⁻ⁿ), where P is the loan amount, i is the monthly rate (annual rate / 12) and n is the number of payments (years × 12).

Total interest is the difference between the sum of all payments and the original loan amount — a longer term lowers the monthly payment but significantly raises total interest paid.

UK lenders don't publish a single unified rate table — the calculator therefore shows market-average rates by fixed period (2-year and 5-year fixes).

Examples: loan amount → monthly payment (default rate, 30 years)

Loan amountMonthly payment
£150,000.00£818.12
£200,000.00£1,090.82
£250,000.00£1,363.53
£300,000.00£1,636.23
£400,000.00£2,181.64
£500,000.00£2,727.05

Frequently asked questions

How is the monthly mortgage payment calculated?

On a repayment basis, using M = P × i / (1 − (1+i)⁻ⁿ). The payment stays constant; only the interest/capital split within it changes.

What is total interest?

The difference between the sum of all payments over the full term and the original loan amount.

Fixed or tracker rate — which is typical in the UK?

A 2-year or 5-year fix is typical. After it ends, you move onto the lender's standard variable rate (SVR) unless you remortgage.

What is an ERC (Early Repayment Charge)?

A fee for repaying early during the fixed-rate period — common on most UK fixed-rate mortgages.

How much can I borrow on my income?

That's answered by the separate mortgage affordability calculator, applying the LTI multiple (4.5–5.5×) and LTV.

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Last updated: 18 July 2026