Most UK lenders will lend 4 to 4.5 times your yearly income before tax. On £40,000 that is £160,000 to £180,000. Some go up to 5.5 times for higher earners or certain professions, but only if the monthly payment passes their affordability checks.
The income multiple sets the ceiling. What decides whether you reach it is affordability: your take-home pay, your regular spending and whether you could cope if rates rose. The figures below use a 4.5% interest rate over 25 years as a worked example; plug in real quotes to get your own numbers.
Income multiples: the quick answer
Take your gross salary and multiply. A single buyer on £40,000 is typically offered £160,000 at 4 times, £180,000 at 4.5 times and, at the top end, £220,000 at 5.5 times. Joint applicants add their incomes first: two people on £35,000 each are treated as £70,000, which at 4.5 times is £315,000.
Borrowing at 4.5 times income, by salary. The highlighted bar is the £40,000 example used throughout this guide.
What each salary can borrow
The last column matters most. It is the monthly payment as a share of take-home pay, after income tax and National Insurance, with no student loan or pension.
| Salary | At 4x | At 4.5x | Monthly at 4.5% | Of take-home |
|---|---|---|---|---|
| £25,000 | £100,000 | £112,500 | £625 | 35% |
| £30,000 | £120,000 | £135,000 | £750 | 36% |
| £35,000 | £140,000 | £157,500 | £875 | 37% |
| £40,000 | £160,000 | £180,000 | £1,001 | 37% |
| £50,000 | £200,000 | £225,000 | £1,251 | 38% |
| £60,000 | £240,000 | £270,000 | £1,501 | 40% |
| £80,000 | £320,000 | £360,000 | £2,001 | 42% |
| £100,000 | £400,000 | £450,000 | £2,501 | 44% |
On £40,000, a £180,000 mortgage takes 37% of your take-home pay
That share climbs from 35% on £25,000 to 44% on £100,000. The multiple stays the same, but tax takes a bigger slice of higher salaries, so the payment eats more of each take-home pound. On £40,000 your take-home pay is £2,693 a month (see the full £40,000 after tax breakdown), and £1,001 of it would go on the mortgage.
Affordability and the stress test
Lenders then check what you spend. Credit cards, car finance, childcare, other loans and student loan repayments all reduce what they will lend, because they come out of the same take-home pay. A Plan 2 loan on £40,000 takes £80 a month; the student loan plans guide shows the figure for every plan.
They also stress test: they check you could still pay at a higher rate than the one on offer. If the £180,000 loan were charged at 7.5% instead of 4.5%, the payment would rise from £1,001 to £1,330 a month, which is 49% of take-home pay on £40,000. If your budget cannot absorb that, expect a lower offer.
An agreement in principle is not a mortgage offer. The full check happens after you apply, so do not commit to a price based on the headline multiple alone.
Deposit, term and what it all costs
With a 10% deposit, a £180,000 mortgage buys a £200,000 home. As a first-time buyer you would pay £0 stamp duty on that, as the stamp duty on £200,000 page shows. The joint buyers above could reach £350,000, with £2,500 to pay; the first-time buyer stamp duty guide explains why.
Over 25 years at 4.5%, the £180,000 loan costs £120,150 in interest on top of the money borrowed. For the first years most of each payment is interest, and the balance falls slowly:
A longer term lowers the payment, which can help you pass affordability, but costs more overall:
| Term on £180,000 | Monthly | Total interest |
|---|---|---|
| 25 years | £1,001 | £120,150 |
| 30 years | £912 | £148,331 |
| 35 years | £852 | £177,781 |
How to borrow more
- Clear or cut debts first. Every monthly commitment lowers the affordability figure.
- Grow the deposit. Saving £400 a month for 4 years at an assumed 4% gives £20,784. Try other amounts in the savings calculator.
- Apply jointly. Two incomes are added together before the multiple is applied.
- Check your pension setup. Salary sacrifice lowers the salary a lender sees; the salary sacrifice guide covers the trade-off.
Run exact figures for any loan, rate and term in the mortgage calculator.
Mortgage calculatorMonthly payments, total interest and what a rate change costs you. Open itQuestions people ask
How much can I borrow on £40,000?
Usually between £160,000 and £180,000, at 4 to 4.5 times income. Some lenders go to 5.5 times, or £220,000, for certain professions or higher earners.
Do lenders use my salary before or after tax?
Before tax for the income multiple, but the affordability check looks at what you actually take home and what goes out each month.
How much can a couple borrow?
Lenders usually add both incomes together. Two people on £35,000 each could borrow around £315,000 at 4.5 times their joint income.
What is a mortgage stress test?
A check that you could still pay if rates rose. Lenders test the payment at a rate above the one you will actually pay, so a loan that looks affordable today can still be turned down.
