Mortgage Affordability Calculator United Kingdom

Before you fall for a house, it helps to know what a lender will lend you. UK mortgage affordability depends mainly on your income and an income multiple, reduced by existing commitments and added to by your deposit. This calculator turns those into a maximum property price, so you can house-hunt in the right range.

How lenders decide what you can borrow

Most UK lenders start with an income multiple, typically 4 to 4.5 times your annual income, and up to 5 or 5.5 times for higher earners or certain professions. Lending at 4.5 times income or more is limited across the market by Bank of England rules, which is one reason higher multiples are harder to get. On a joint application the incomes are combined, so two average salaries can borrow much more than one. Existing debts such as loans, car finance and credit cards reduce what you can borrow, because they use income that would otherwise go on the mortgage. Add your deposit to the maximum loan for the maximum price you can target.

Income multiples in practice

The multiple is a rule of thumb, not a guarantee. Lenders also test affordability against your actual outgoings and against higher interest rates, so two people on the same salary can be offered different amounts depending on their spending, dependants and credit history. Adjust the multiple to model a cautious lender (4 times), a mainstream one (4.5 times) or a generous one (5 times or more) and see the range.

The role of your deposit

Every pound of deposit is a pound less to borrow, so it adds directly to the price you can afford. It also sets your loan-to-value (LTV), the mortgage as a percentage of the price. The best rates go to lower LTVs, with cheaper deals typically below 90%, 85%, 80% and 75%. The calculator shows both your maximum price and the resulting LTV, so you can see whether a bigger deposit would move you into a better band.

A worked example

You earn £40,000 and have saved a £40,000 deposit. At 4.5 times income you could borrow up to £180,000, a maximum property price of £220,000 at about 82% LTV. Add a second applicant earning £20,000 and the combined £60,000 supports £270,000 of borrowing: a £310,000 property with the same deposit, at about 87% LTV. If instead you pay £500 a month on a car loan, £6,000 a year comes off your income first, cutting the maximum loan to £153,000 and the maximum price to £193,000.

How to use the calculator

Enter your annual income and deposit and choose an income multiple. Use the advanced options to add a second applicant’s income and any monthly debt payments. The result shows the maximum you could borrow, the maximum property price, the multiple used, the loan-to-value and your deposit as a percentage. Use it to set a budget, to see the benefit of clearing a debt or saving more, or to check whether a joint application brings the homes you want within reach.

Assumptions and limitations

This is an indicative estimate, not a mortgage offer or a decision in principle. It applies a simple income multiple and a rough adjustment for debt. A lender’s assessment is more detailed, testing your income against committed and discretionary spending, dependants, the mortgage term and a higher notional interest rate. The calculator does not account for credit score, employment type (lenders usually average recent years’ profits for the self-employed), benefits income, the property type or lender-specific limits. Confirm with a lender or broker before committing. The typical income multiple is stored as a parameter and reviewed periodically.

About This Mortgage Affordability Calculator

Use this mortgage affordability calculator to get an instant, accurate estimate. The figures follow official guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.