# Mortgage Calculator UK 2026/27

> Work out monthly mortgage repayments and affordability from your take-home salary. Covers repayment and interest-only loans for 2026/27.

Thinking about buying a home or switching mortgage? Enter the loan amount, interest rate,
and term to see your monthly repayments, total interest paid, and full repayment schedule. This mortgage calculator shows monthly repayments and affordability based on your salary and take-home pay, covering repayment and interest-only loans.

A mortgage is usually the largest financial commitment most people make. Monthly repayments depend on three things: how much you borrow, the interest rate and the term. This calculator shows repayment and interest-only figures, and how a small change in rate changes both your monthly cost and the total interest you pay over the life of the loan.

## How monthly repayments are calculated

On a repayment mortgage, each payment covers the month's interest plus some of the capital. Early on, most of the payment is interest; over time the balance shifts until the loan is cleared. On an interest-only mortgage, you pay only the interest and repay the capital separately at the end — cheaper monthly, but you still owe the full loan.

On a £250,000 repayment mortgage at 4.5% over 25 years, the monthly payment is roughly £1,390 and total interest is about £167,000. Stretch the term to 35 years and the monthly payment falls to about £1,183, but total interest rises to roughly £247,000 — a costly trade-off.

## How much can you borrow?

Most UK lenders cap borrowing at around 4 to 4.5 times your annual income, then stress-test affordability against your outgoings. Self-employed applicants, those with variable income, and anyone with significant existing debt will typically be offered less. A rough rule of four times income gives a starting point, but always confirm with a lender or broker.

## Why the rate matters so much

Because a mortgage runs for decades, interest rate changes compound. A 1% difference on a £250,000 loan over 25 years is tens of thousands of pounds. This is why fixing a rate — trading flexibility for certainty — is a genuine decision rather than a default. The calculator shows how different rates affect both the monthly cost and the total.

Model your own mortgage above. Understanding your take-home pay first helps — see our [take-home pay calculator](https://salarycal.co.uk/take-home-pay-calculator/).

## Frequently asked questions

### How much can I borrow for a mortgage?

Most UK lenders allow you to borrow around 4 to 4.5 times your annual income. On a £40,000 salary that is roughly £160,000 to £180,000. Lenders also check affordability against your take-home pay and existing debts.

### How are mortgage repayments calculated?

For a repayment mortgage, each monthly payment covers the interest on the outstanding balance plus some of the capital. As the balance falls, the interest portion shrinks and the capital portion grows. The calculator shows the full schedule.