How does the mortgage affordability calculator work?

The borrowing calculator uses standard UK income multiples, the same method most lenders apply, to estimate how much you could borrow based on your income, any joint applicant’s income, and your monthly debt commitments. It shows results across a range of income multiples (3.5× to 5.5×) so you can see how different lenders might assess your case.

The repayment calculator uses a standard compound interest formula to calculate your estimated monthly payment based on the loan amount, interest rate, and mortgage term. You can switch between repayment and interest-only to compare the two.

What affects how much I can borrow?

• Income, total household income is the primary driver. Most lenders offer 4–4.5× annual income. Some specialist lenders stretch to 5–5.5× for certain applicants.
• Outgoings, regular debt commitments (car finance, loans, credit cards) reduce the amount lenders are willing to advance.
• Credit score, a strong credit profile improves your access to higher income multiples and better rates. Adverse credit limits your options but does not prevent you from getting a mortgage.
• Deposit, a larger deposit improves your loan-to-value ratio, unlocking lower rates and a wider range of lenders.
• Employment type, self-employed applicants, contractors, and those with variable income may find that different lenders assess their income very differently. The right broker can make a significant difference to the amount you can borrow.

Are the figures accurate?

These calculators provide estimates based on standard assumptions. The actual mortgage you are offered will depend on a full lender assessment of your circumstances, credit profile, and the specific property. For a precise figure, speak to one of our advisers, we will assess your situation against the actual criteria of 90+ lenders and give you an accurate borrowing figure at no cost.