How much can I borrow for a mortgage? (2026/27)

Your maximum mortgage is not simply a multiple of your salary. Lenders use a two-part test: an income multiple to set an initial ceiling, and an affordability assessment (stress-tested monthly payments versus monthly outgoings) to verify you can actually service the debt.

This guide explains both parts, gives worked examples, and shows you how to use the mortgage affordability calculator to model your position.

Not financial advice. Mortgage lending criteria vary significantly between lenders and change over time. Always speak to an independent mortgage adviser (FCA regulated) before making a purchase decision. Sources: FCA PS21/13 responsible mortgage lending; Bank of England LTI flow limit guidance; individual lender criteria.

1. The income multiple — your starting ceiling

The most widely used rule of thumb is 4 to 4.5 times gross annual income for a single applicant. For joint applicants, lenders typically use the combined income:

| Gross income | 4× | 4.5× | 5× | |---|---|---|---| | £35,000 | £140,000 | £157,500 | £175,000 | | £50,000 | £200,000 | £225,000 | £250,000 | | £75,000 | £300,000 | £337,500 | £375,000 | | £100,000 | £400,000 | £450,000 | £500,000 | | £60,000 joint (£35k + £25k) | £240,000 | £270,000 | £300,000 |

The Bank of England limits lenders to no more than 15% of their new residential mortgage lending at LTI ratios above 4.5× income. This is a portfolio-level cap — individual borrowers above 4.5× are possible, but less common.

Professional and higher earner multiples

Some lenders offer higher income multiples (5×, 5.5×) to:

• High earners (often £75,000+ single, £100,000+ joint)
• Professionals in defined occupations (doctors, dentists, solicitors, accountants, surveyors, architects)
• Borrowers with a large deposit (≥25% LTV)
• Borrowers with very low committed outgoings

2. The affordability stress test

Beyond the income multiple, lenders run a monthly affordability test using a stressed interest rate. This checks whether you could still afford repayments if rates rose.

Since the FCA removed the mandatory +3% stress test buffer in 2022 (PS21/13), lenders apply their own policies — but most use a stress rate of 2–3% above either:

• The reversion rate (standard variable rate), or
• The Bank of England base rate plus a margin

Example: If you take a 5-year fixed rate at 4.5% and the lender's SVR is 7.5%, they may test affordability at 7.5% (the SVR, which is already above many internal stress floors).

The monthly repayment at the stress rate must typically be below 35–45% of net monthly income (the exact threshold varies by lender).

3. Loan-to-Value (LTV) and deposit

The Loan-to-Value ratio is the mortgage as a percentage of the property's value. A higher LTV means more risk for the lender, so rates are typically higher:

| LTV | Deposit | Rate tier | |---|---|---| | 95% | 5% | Highest rates; limited lenders | | 90% | 10% | Better rate availability | | 75% | 25% | Good mainstream rates | | 60% | 40% | Best available rates |

For a property worth £300,000 with a 10% deposit (£30,000), you need a mortgage of £270,000 at 90% LTV.

Don't forget the other buying costs — stamp duty, solicitor fees (£1,500–£3,000), survey (£500–£1,500), and mortgage arrangement fees. Budget for these in addition to your deposit, or they reduce the size of the deposit you can put down.

4. How outgoings affect what you can borrow

Lenders look at your committed monthly outgoings alongside income. Items typically counted:

• Existing loan and credit card repayments — credit card minimum payments count, not just what you actually pay
• Car finance — PCP, HP and personal loans
• Student loan deductions — these show on payslips and are hard commitments
• Child maintenance court orders
• Childcare costs (some lenders, not all)

High outgoings can reduce your offer significantly. If you have a £400/month car finance payment, a lender using a 4× multiple might reduce their offer by up to £19,200 (approximately £400 × 12 × 4 = £19,200 in income equivalent).

Clearing smaller debts before applying can meaningfully increase your borrowing capacity.

5. Joint mortgages

For a joint mortgage, lenders combine both incomes. However, they also combine both sets of committed outgoings. The income multiple is applied to the combined gross salary:

Example: Two applicants earning £35,000 and £30,000 = £65,000 combined. At 4.5×, maximum borrowing is £292,500. Outgoings of £500/month between them would reduce the affordable repayment figure in the stress test.

Joint mortgages also mean joint liability — both borrowers are equally responsible for the full debt.

Related guides

• Stamp duty explained: SDLT, LBTT and LTT — stamp duty adds to your upfront buying costs
• How is take-home pay calculated? — your net income is key to the affordability stress test