Mortgage Affordability Calculator

What you could borrow on your salary

A rough guide at 4.5×, the upper end of the usual 4–4.5× range, with repayments shown over 25 years at 4.5%. These are single-applicant figures before any deductions for debts or dependants — enter your own numbers above for a figure that accounts for them.

Joint applicants combine both incomes before the multiple is applied, so two £30,000 salaries are assessed as £60,000 — not as two separate £30,000 cases.

For a fuller breakdown on one salary — deposit scenarios, what price range it reaches and what pulls the figure down — see £30,000, £40,000, £50,000, £60,000, or any other salary.

What the stress test actually checks

A lender does not only ask whether you can afford today’s payment. It asks whether you could still afford it if your rate went up when your fixed period ends. That means running your mortgage at a materially higher rate than the one you are being offered and checking the answer still works — the calculator above models this at 1, 2 and 3 percentage points above your rate, because that is the band lenders typically apply.

The consequence catches people out. A two-year fix at a headline rate is assessed against a much higher one, so the cheap deal on the comparison site does not buy you a bigger mortgage. What raises the number a lender will stress-test successfully is a longer term, a larger deposit, or fewer commitments — not a lower advertised rate.

Stress-testing rules have changed more than once in recent years and individual lenders set their own margins within them, so treat any specific figure — including ours — as an estimate rather than a decision. A lender’s own agreement in principle is the only number that binds them.

How your deposit changes what you pay

Deposits matter twice. They raise your ceiling pound for pound, and they move you between loan-to-value bands, where the pricing actually lives. Lenders price in tiers — commonly at 95%, 90%, 85%, 80%, 75% and 60% LTV — and each threshold you cross downwards tends to unlock a cheaper rate.

That makes the last few thousand pounds of saving disproportionately valuable if it takes you over a band boundary. Going from 95% to 91% LTV changes very little — you are in the same band throughout — while going from 90.5% to 89.9% moves you into a different price list for the sake of a fraction of a percent. It is worth checking where your deposit lands against the band edges before you make an offer, rather than after.

Below 10% deposit, the choice of lender narrows sharply and rates rise. Above 25%, the improvements start to flatten out — the difference between a 25% and a 40% deposit is usually smaller than the difference between 5% and 10%.

What reduces the amount you can borrow

The income multiple is a ceiling, not a promise. The affordability assessment then subtracts your committed monthly spending, and each of these reduces borrowing by considerably more than its monthly cost — because the lender is capitalising that payment over the whole term:

• Credit commitments — loans, car finance, buy-now-pay-later and the balance on credit cards, whether or not you clear them monthly.
• Childcare — often the single largest deduction for applicants with pre-school children, and the one people most often forget to declare.
• Student loans — assessed from your payslip deduction, so the plan you are on and your income both matter.
• Dependants — most lenders apply a per-child allowance regardless of what you actually spend.
• Ground rent and service charges — on a leasehold flat these are treated as a commitment, which is why the same salary buys less leasehold than freehold.

Clearing a small loan before you apply can therefore raise your borrowing by several times the balance you paid off. It is usually the highest-return thing an applicant can do in the three months before an application — more than a marginal pay rise, and considerably more than shopping for a slightly lower advertised rate.

Self-employed, contract and variable income

If you are self-employed, a lender generally wants two years of accounts or SA302s and will work from an average of them — or, if your figures are falling, the lower year. A minority will consider one year’s trading. Company directors should expect salary plus dividends to be assessed rather than retained profit, though some lenders will look at net profit instead, which can produce a dramatically different answer for the same business.

Bonus, commission and overtime are usually taken at 50% to 100% depending on how consistent they have been, and day-rate contractors are often assessed on an annualised day rate rather than accounts. Because these treatments vary so widely between lenders, variable income is the case where a broker earns their fee most clearly: the spread between the most and least generous lender on the same application can be six figures.

Borrowing is only half the budget

The mortgage tells you what you can offer. It does not tell you what you need in the bank on completion day. Stamp duty — or LBTT in Scotland and LTT in Wales, which use different bands entirely — conveyancing, searches, a survey, removals and any lender or broker fee all come out of cash, not out of the loan.

A deposit that exactly hits your target price is therefore not enough: spending it all on the purchase price leaves nothing for the costs that land alongside it. Our cost of buying a house calculator totals those, and the deposit calculator works backwards from a target price to what you still need to save.

Frequently asked questions

How much can I borrow for a mortgage?

Most UK lenders offer between 4 and 4.5 times your annual gross income. For example, on a £50,000 salary you could borrow £200,000–£225,000. Joint applications combine both incomes. Some specialist lenders may offer higher multiples for professionals or high earners.

What is a mortgage stress test?

A stress test checks whether you could still afford repayments if interest rates rose significantly — typically 3 percentage points above your actual rate. If you're borrowing at 4.5%, the lender checks you could afford payments at 7.5%. This is a regulatory requirement to protect borrowers.

Does my deposit affect how much I can borrow?

Your deposit doesn't directly change the income multiple, but a larger deposit means you need to borrow less. A 10% deposit on a £300,000 property means borrowing £270,000, while 20% means borrowing only £240,000. Larger deposits also unlock better interest rates.

What percentage of my salary should go to mortgage payments?

Financial advisors generally recommend that your mortgage payment shouldn't exceed 28–35% of your net monthly income. Above 35% is considered stretched — you may struggle with unexpected costs, maintenance, or interest rate rises.

How much mortgage can I get on a £50,000 salary?

At the 4.5× multiple most UK lenders work to, a £50,000 salary supports roughly £225,000 of borrowing — about £1,251 a month over 25 years at 4.5%. Add your deposit on top for the maximum property price. Credit commitments, childcare and dependants all reduce it from there.

How much do I need to earn to buy a £300,000 house?

Work backwards from the loan, not the price. With a 10% deposit you would be borrowing £270,000, which needs roughly £60,000 of income at 4.5× — or about £50,000 if you can put down 25%. A bigger deposit lowers the income you need as well as the amount you borrow.

Can I get a mortgage with existing debt?

Yes, but it reduces what you can borrow by more than the debt itself. Lenders capitalise your monthly commitment over the mortgage term, so a modest car finance payment can cost you tens of thousands of borrowing capacity. Clearing a small balance before you apply is often the single most effective thing you can do to raise your offer.

Do lenders use gross or net income?

The income multiple is applied to gross annual income — your salary before tax. The affordability assessment then works from your net position, subtracting tax, National Insurance, student loan deductions and your committed monthly spending. Both matter: gross sets the ceiling, net decides whether you reach it.

How much can I borrow if I'm self-employed?

The same multiples apply, but the income figure is derived differently: typically an average of two years' accounts or SA302s, or the lower year if your figures are falling. Company directors are usually assessed on salary plus dividends, though some lenders use net profit instead — which can change the answer substantially for the same business.

Does a longer mortgage term let me borrow more?

Usually yes, because it lowers the monthly payment the affordability assessment has to accommodate. It also increases the total interest you pay over the life of the loan, and lenders will look at whether the term runs past your expected retirement age. It buys headroom now at a real cost later.