About the UK Mortgage Affordability Calculator
UK lenders usually cap mortgage borrowing at a multiple of gross annual income — typically 4 to 4.5 times, and up to 5 or 5.5 times for higher earners or certain professions — then reduce it for existing credit commitments such as car finance, loans and credit cards. This calculator estimates your borrowing range on that basis, adds your deposit to show the maximum property price, and calculates the monthly repayment.
It works for single applicants and couples (enter both salaries) and is handy before you speak to a broker, when setting a house-hunting budget, or when checking whether paying off a loan first would help. It also shows the payment if rates rose by a few percentage points, because lenders must check you could still afford the mortgage if rates increase.
The model treats each £1 of annual credit commitments as reducing your income by £1 before the multiple is applied, a simplified version of how lenders assess outgoings. Real affordability models also weigh dependants, childcare, credit history and bonus income, so treat the result as a guide rather than a mortgage offer.
With the default inputs, the estimated maximum mortgage is £191,700.00. Change any value above to recalculate instantly.
How to use the uk mortgage affordability calculator
- 1Enter your gross annual salary and, for a joint mortgage, your partner’s.
- 2Add other regular income a lender would accept.
- 3Enter monthly credit commitments such as loans and car finance.
- 4Pick an income multiple and enter your deposit.
- 5Check the maximum mortgage, property price and repayment — including the stressed payment.
Formula and method
Gross income is the sum of both applicants’ salaries and any other regular income you enter. Annual credit commitments (monthly payments × 12) are subtracted, and the result is multiplied by the chosen income multiple to give the estimated maximum loan. Adding your deposit gives the highest price you could pay; LTV is the loan divided by that price.
The monthly repayment uses the standard capital-and-interest formula M = P × r(1 + r)^n ÷ ((1 + r)^n − 1) over the term. The stressed payment repeats the calculation at your rate plus the stress add-on, showing what the same loan would cost if rates rose. Loan-to-income is the maximum loan divided by total gross income.
- Multiple
- Lender income multiple (e.g. 4.5× gross income)
- Commitments
- Monthly payments on existing credit
- M, P, r, n
- Monthly payment, loan, monthly rate and number of months
Worked examples
£45k salary, £200/month car finance, £30k deposit
Annual commitments of £2,400 reduce £45,000 to £42,600, and 4.5 × £42,600 = £191,700. With a £30,000 deposit the maximum price is £221,700 (86.5% LTV). Repayments are £971 a month at 4.5% over 30 years, rising to £1,340 if rates were 3 points higher.
Couple earning £40k and £35k, £50k deposit
Joint income of £75,000 with no commitments supports 4.5 × £75,000 = £337,500. Adding the £50,000 deposit gives a budget of £387,500, with repayments of about £1,710 a month at 4.5% over 30 years.
£60k earner on a 5.5× professional scheme
Commitments of £400 a month (£4,800 a year) reduce income to £55,200, and 5.5 × £55,200 = £303,600. That is 5.06 times gross income, so only lenders with professional or high-income schemes would offer it.
Frequently asked questions
How much can I borrow on a mortgage in the UK?+
Most lenders offer around 4 to 4.5 times gross annual income, adjusted for your outgoings and credit commitments. Some offer 5 to 5.5 times for higher earners or professions such as doctors and solicitors, subject to their own affordability model.
Do lenders use joint income for a mortgage?+
Yes. For a joint mortgage lenders add both applicants’ incomes and apply the multiple to the total, after deducting both people’s commitments. Each applicant is jointly responsible for the whole loan.
What is the 4.5 times income limit?+
The Bank of England’s Financial Policy Committee limits each lender so that no more than 15% of its new residential mortgages are at loan-to-income ratios of 4.5 or higher. Loans above 4.5× exist but are rationed, so criteria are stricter.
Does a mortgage stress test still apply?+
The Bank of England withdrew its specific 3-percentage-point affordability test in 2022, but FCA rules still require lenders to consider the effect of likely future rate rises on affordability. Lenders typically test at a rate a few points above the product rate.
How can I increase how much I can borrow?+
Paying off loans and credit cards, adding a second applicant, choosing a longer term, saving a larger deposit and reducing regular outgoings can all raise the amount a lender will offer. Better credit history can also open up lenders with higher multiples.
Results are estimates for educational purposes and are not financial advice. Rates, fees and terms vary — confirm with your lender or a licensed advisor before making decisions.