How much you could borrow, the monthly cost, and a stress test if rates rise. Income multiples are the typical range lenders use as a starting point — every lender runs its own affordability assessment on your income, debts and spending, so this is a guide, not a promise or an offer.
Rule of thumb used here: your yearly debts and childcare (£0) come off your income before the multiple is applied. Lenders look at each commitment individually, so treat the result as a range, not a verdict.
Lenders often prefer payments below about a third of income. Each lender decides — many also cap lending around 4.5× income, with higher multiples reserved for higher earners and certain professions.
| Scenario | Rate | Monthly |
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| Rate | Monthly | Share of gross income |
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Lenders are required to check you could still afford the mortgage if rates rise — this is that check, on your numbers. The stressed rows assume the higher rate for the whole remaining term; a fixed deal shields you until it ends, then the payment could jump to whatever rates are then.
| Term | Monthly | Total interest |
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A longer term cuts the monthly payment but the loan is outstanding for more years, so more interest accrues. Shorter terms usually need a bigger monthly budget — and many lenders cap the term by your age at the end of it.
| Multiple | Borrow | Monthly |
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Multiples apply to income after debts, the way this calculator models it. The 4.5× row is where most mainstream lending sits; 5× and above exists but is not typical for everyone.
How much you could borrow for a UK mortgage, what it would cost a month, and whether you could still afford it if rates rose — from your income, deposit and debts.
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Estimate your borrowing power from typical lender income multiples, then check the monthly cost, the loan to value and whether you could still afford the payment if rates rose — plus the stamp duty and total cash the purchase needs.
Two incomes of £60,000 and £25,000, no monthly debts, a £60,000 deposit and a 4.5× multiple: borrowing comes to £382,500 and the property to £442,500 — an 86.4% loan to value. At 4.8% over 25 years the payment is £2,192 a month, 30.9% of gross income; at 7.8% it would be £2,902. Stamp duty on that property (England & Northern Ireland, main home) is £12,125, so the cash needed on top of the mortgage is £72,125.
Borrowing is your income after a year of debt and childcare payments, multiplied by the multiple you choose — multiples are the typical lender starting range, not a rule any lender must follow. The monthly payment is the standard repayment (annuity) formula at your rate and term; the stress rows re-run the same formula at higher rates for the whole term. The stamp duty figure reuses this site’s verified SDLT calculation for an England & Northern Ireland main home, and the total cash is deposit plus that tax when the toggle is on.
As a starting point, most mainstream lenders lend around 4 to 4.5 times income — £85,000 of joint income points to roughly £340,000–£382,500 before debts are considered. Some lenders go to 5× or 5.5× for higher earners, large deposits or certain professions, but it is the exception, not the norm — and the final say is the lender’s full affordability assessment, not the multiple alone.
Lenders must check you could still afford the mortgage if interest rates rise. The Stress test tab shows your payment at 1%, 2% and 3% above today’s rate — on the example loan, a 3% rise takes the payment from £2,192 to £2,902 a month, 41% of gross income. If a stressed payment would break your budget, a smaller loan or a longer fix is the safer plan.
Yes — card balances, loans, finance and childcare all come out of what a lender thinks you can afford. This calculator models it simply: twelve months of those payments come off your income before the multiple applies, so £400 a month of debts cuts the example borrowing from £382,500 to £360,900. Clearing small debts before applying often helps more than the same money added to the deposit.
Stamp duty, mainly: £12,125 on a £442,500 main home in England. Then legal and survey fees and moving costs, which vary. The Total cash needed card adds the deposit and stamp duty together; first-time buyers pay less or nothing (no SDLT up to £300,000), and Scotland and Wales have their own taxes.
It lowers the loan to value, and lenders price in LTV bands — crossing below 90%, 85%, 80% or 75% often unlocks cheaper deals. Try the bigger-deposit button: the same borrowing with £10,000 more deposit drops the example from 86.4% to about 84.5% LTV. The borrowing itself is set by income, so the payment only changes if the rate does.
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