Before you fall in love with a property on Rightmove, it pays to know what a lender is likely to offer you. This affordability calculator gives you a realistic estimate of how much you could borrow based on your income, your partner’s income if you are buying together, and your regular financial commitments — so you can search within a price range that is actually achievable.
Mortgage Affordability Calculator
A quick UK estimate of how much a lender might let you borrow, the property price that could put within reach, and what the monthly payment might look like.
Maximum you could borrow (4.5× income)
£202,500
Important: existing debts can reduce the amount a lender offers, because they run their own affordability checks on your full outgoings — so treat these figures as an upper estimate, not a promise. A mortgage broker or a lender’s agreement in principle will give you a firmer number.
How it works: Most UK lenders cap borrowing at around 4.5 times your income (some stretch to 5–5.5× for higher earners or certain professions). We multiply your total household income by 4.5, add your deposit to get a maximum property price, then work out the monthly payment on that loan using your sample rate and term. Borrowing the maximum isn’t always wise — leave room in your budget for bills, insurance and rate rises.
How it works
Enter your gross annual income (and a second income for a joint application), then add your regular monthly commitments: loan and credit card payments, car finance, childcare costs and similar fixed outgoings. The calculator applies a typical UK income multiple to estimate the maximum loan, then adjusts it for affordability — because since the Mortgage Market Review, lenders do not just multiply your salary; they also stress-test whether you could still afford the payments if interest rates rose.
The result is an estimate of your maximum mortgage, which combined with your deposit gives your maximum purchase price.
How the calculation works
Most UK lenders cap borrowing at around 4.5 times your gross annual income. Some will stretch to 5 or even 5.5 times for high earners, certain professional occupations (such as doctors, solicitors and accountants), or borrowers with large deposits — but 4.5× is the sensible planning figure for most people.
On top of the multiple, lenders run an affordability assessment: they look at your committed monthly spending, model your essential living costs, and check the mortgage would still be affordable at a higher “stressed” interest rate. Heavy commitments — a £450 car finance payment, for example — can pull the maximum loan down well below the headline multiple. That is why two households on identical salaries can be offered very different amounts.
Worked example
A couple buying together in Manchester:
- Earner 1: £38,000 a year
- Earner 2: £27,000 a year
- Combined income: £65,000
- Commitments: car finance £260/month, one personal loan £140/month, credit cards paid in full monthly
Step 1 — income multiple: £65,000 × 4.5 = £292,500 maximum loan before affordability checks.
Step 2 — affordability: their committed outgoings of £400 a month reduce what a lender will offer; a realistic outcome might be around £270,000–£285,000.
Step 3 — add the deposit: with £30,000 saved, their maximum purchase price is roughly £300,000–£315,000.
Note the loan-to-value too: borrowing £285,000 on a £315,000 home is about 90% LTV. Dropping to 85% or 75% LTV usually unlocks noticeably cheaper rates, so the deposit size matters twice — once for affordability, once for the interest rate.
Tips
- Clear or shrink commitments before applying. Paying off a small loan or car finance agreement six months before you apply can increase your maximum loan by far more than the balance you cleared, because lenders annualise the monthly payment against your income.
- Check your credit files early. Look at all three UK agencies (Experian, Equifax and TransUnion) months before applying. Fix errors, get on the electoral roll at your current address, and avoid new credit applications in the run-up.
- Do not max out the estimate. Borrowing the absolute maximum leaves no slack for rate rises or life changes. Many buyers are more comfortable borrowing 4–4.25× income even when 4.5× is offered.
- Joint income counts, but so do joint debts. A partner’s income boosts the multiple; their loan and car payments drag the affordability back down. Run the figures both ways if one of you has heavy commitments.
- Get an Agreement in Principle. Once you have an estimate here, a broker or lender can issue an AIP based on a fuller assessment. Estate agents take offers far more seriously with one attached.
FAQ
How many times my salary can I borrow?
Typically up to 4.5× your gross annual income with mainstream UK lenders. Some stretch to 5–5.5× for high earners, professionals or low loan-to-value applications, and most lenders cap lower multiples for smaller incomes or interest-only loans.
Does my partner’s income count on a joint mortgage?
Yes. Lenders use your combined gross income for the multiple and your combined commitments for affordability. Both applicants’ credit histories are also checked.
Do credit card balances reduce what I can borrow?
Balances you clear in full each month usually have little impact. Balances you carry and pay gradually count as committed spending and reduce your maximum loan — as a rough rule, lenders may assume a monthly payment of around 3% of the outstanding balance.
What deposit do I need?
The minimum for many lenders is 5% of the purchase price (95% LTV), but rates improve significantly at 90%, 85% and 75% LTV. A bigger deposit also widens the pool of lenders willing to lend.
Can I get a mortgage if I am self-employed?
Yes, but you will normally need one to three years of accounts or SA302 tax calculations. Most lenders use your average profit over the last two or three years rather than your best year, which can lower the multiple you effectively receive.
This calculator is for guidance only and does not constitute mortgage or financial advice. Your home may be repossessed if you do not keep up repayments on your mortgage.