Mortgage Affordability Calculator

Estimate how much you could borrow for a mortgage from one or two incomes, your monthly commitments and your deposit, using income multiples.

Reviewed by Dany, RightSums team · Updated

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personal-finance · Daily life · UK

Enter one or two yearly incomes before tax, any monthly commitments such as loans or car finance, and your deposit. The calculator gives an indicative borrowing range using income multiples, set to 4 and 4.5 times income by default, and adds your deposit to show a property price range. You can change both multiples. Monthly commitments are taken off your yearly income before the multiple is applied, a rough rule this tool uses rather than a lender formula. You also see the loan-to-value and an estimated monthly payment at a rate and term you choose. This is a guide only. Lenders run their own affordability checks on your income, spending and credit history, and may offer more or less.

Accepted inputs

  • Your yearly income before tax
  • Second applicant's income
  • Monthly commitments
  • Deposit
  • Lower and upper income multiples
  • Interest rate and term for the payment estimate

Outputs

  • Indicative borrowing range
  • Property price range
  • Loan-to-value at each multiple
  • Estimated monthly payment

How to use the Mortgage Affordability Calculator

  1. Enter your yearly income before tax and, if you are buying with someone, their income too.
  2. Add your monthly commitments, such as loan, car finance or credit card repayments, and your deposit.
  3. Adjust the income multiples if you want to test a different range, and set a rate and term for the payment estimate.
  4. Read the indicative borrowing range, the property price range and the estimated monthly payment.

Frequently asked questions

How much can I borrow for a mortgage on £45,000?

At 4 to 4.5 times income, a £45,000 salary gives an indicative £180,000 to £202,500. With a £30,000 deposit that points to homes of about £210,000 to £232,500. At 4.5% over 25 years, the top figure would cost about £1,125.56 a month. Lenders' own checks decide the real amount.

How much can we borrow on a joint income?

Add both incomes together. Earning £40,000 and £30,000 with £250 a month of commitments, this tool uses £67,000 a year (£70,000 less £3,000). At 4 to 4.5 times that, the range is £268,000 to £301,500, or £308,000 to £341,500 with a £40,000 deposit.

How many times my salary can I borrow?

Each lender sets its own limit after checking your finances, so there is no single answer. This tool starts at 4 and 4.5 times income, and you can change both. The Bank of England's Financial Policy Committee aims to keep loans at 4.5 times income or more to no more than 15% of new mortgages.

Do monthly debts reduce how much I can borrow?

Yes, lenders look at your regular spending and debts as well as income. This tool takes a simple approach: it subtracts 12 months of your commitments from your yearly income before applying the multiple. £300 a month off a £45,000 salary leaves £41,400, cutting the 4.5 times figure to £186,300.

Is this what a lender will offer me?

No. It is an indicative range based on income multiples. Lenders run their own affordability checks, looking at income, spending, credit history, the deposit and the rate on the deal, and they may offer more or less. Use the figure to plan a budget, then check with a lender or broker.

Sources

The rates and rules in this tool come from:

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