Mortgage Affordability Calculator (2026)

How much can you actually borrow? UK lenders apply a Loan-to-Income (LTI) cap — typically 4.5× combined gross annual income, with selected lenders going to 5× for higher earners. Add deposit on top to get your maximum purchase price.

What you can borrow

4.0× LTI scenario

£230,000

Max loan £200,000 · monthly £1,091

4.5× LTI scenario

£255,000

Max loan £225,000 · monthly £1,228

5.0× LTI scenario

£280,000

Max loan £250,000 · monthly £1,364

Most UK lenders cap at 4.5× LTI for joint income up to about £100k combined. Above that, selected lenders go to 5× with strong credit + low outgoings. Real affordability also depends on monthly outgoings (loans, childcare, credit), credit profile, and the FCA stress test (rates +3% scenario).

How UK mortgage affordability really works

The Loan-to-Income (LTI) cap

The Bank of England's Financial Policy Committee limits any one lender to no more than 15% of new mortgages above 4.5× LTI. So 4.5× is the working ceiling for most applicants, with the headroom reserved for high-income / low-debt cases. Joint income counts in full.

The FCA stress test

Lenders must check your finances would still hold up if your interest rate rose by 3 percentage points (or 1 percentage point above the lender's reversion rate, whichever is higher). At 4.32% that means stress-testing at ~7.32%. Your monthly outgoings have to fit the budget at the stressed payment.

What lenders look at

Gross annual income from employment (basic + reliable bonus). Self-employed: usually 2-3 years of accounts.
Outgoings: loans, credit-card balances, childcare, school fees, car finance.
Credit profile: arrears, defaults, CCJs in the last 6 years.
LTV: the loan as % of property price. Lower LTVs unlock cheaper rates.

Related tools

This is an indicative tool, not an Agreement in Principle. Your actual borrowing power depends on the lender's underwriting criteria, your credit profile, outgoings and stress-test outcome. Speak to a regulated mortgage broker for a real-world assessment. Source: Bank of England's FPC affordability guidance and the FCA mortgage market rules.