UK Mortgage Borrowing Calculator
Get an instant estimate of how much you could borrow based on income, commitments, term, stress rate, deposit, and loan-to-value (LTV).
This is an indicative UK affordability tool, not a lender decision in principle.
How much mortgage could I borrow in the UK?
Most UK lenders estimate borrowing using two broad checks: an income multiple (often around 4.0x to 4.5x, sometimes higher), and an affordability assessment that looks at your monthly outgoings and whether you could still afford the mortgage if rates rise. The realistic figure is usually the lower result from those two methods.
That means your salary matters, but so do credit card balances, car finance, loans, childcare, and your chosen mortgage term. A larger deposit can also help by reducing loan-to-value (LTV), which can improve lender appetite and product choice.
How this calculator works
1) Income-based borrowing
We total eligible income (including 50% of bonus/commission), then multiply by your selected income multiple. This mirrors the common first-pass lender approach.
2) Payment-based affordability
We estimate a maximum monthly mortgage payment using a chosen percentage of gross monthly income, minus your monthly credit commitments. Then we convert that payment into a maximum loan amount using your stress rate and term.
3) Deposit and LTV cap
We apply your selected maximum LTV to ensure the borrowing remains realistic for your deposit size. If your deposit is small, LTV can become the limiting factor even when income looks strong.
What affects your borrowing amount most?
- Gross income: Higher stable income generally increases borrowing.
- Existing monthly debt: Loans, finance, and revolving credit reduce affordability.
- Mortgage term: A longer term can increase borrowing by reducing monthly repayment pressure.
- Stress test rate: Higher assumed rates usually reduce maximum loan size.
- Deposit size: Bigger deposits can unlock better LTV bands and more options.
- Credit profile: Missed payments and high utilisation can reduce lender appetite.
Example UK scenarios
Single applicant
If you earn £45,000 and a lender uses 4.5x, the income-based figure is roughly £202,500. But if monthly commitments are high, affordability could pull this down.
Joint application
Two applicants earning £38,000 and £30,000 may look stronger on income multiples, but childcare and car finance can materially change the final result.
High income, low deposit
Even with excellent salaries, a small deposit may cap borrowing due to maximum LTV rules. In many cases, increasing the deposit by even a few thousand pounds can widen options.
Practical ways to improve how much you can borrow
- Reduce unsecured monthly commitments before applying.
- Avoid taking new finance in the months leading up to application.
- Check and clean your credit files with UK credit reference agencies.
- Increase deposit where possible (savings, family gift, or equity).
- Consider a longer term if appropriate (understanding total interest trade-off).
- Use a mortgage broker to access lender-specific criteria and niche policies.
Important notes for UK buyers
Real lender underwriting is more detailed than any online calculator. A bank or broker may assess:
- Employment type (PAYE, self-employed, contractor, probation period)
- Income evidence (payslips, P60s, SA302s, accounts)
- Household expenditure and dependants
- Property type and postcode risk
- Age at end of term and retirement income planning
Use this page as a planning tool, then seek a formal Decision in Principle (DIP) for a more accurate figure.
FAQ
Do all lenders use 4.5 times income?
No. Many use around that level, but some offer 5x or more for certain professionals, high earners, or low-risk cases.
Can I get a mortgage with a 5% deposit in the UK?
Yes, in some cases. That usually means up to 95% LTV products, subject to lender criteria and affordability.
Does student loan reduce borrowing?
Potentially yes. Lenders often include student loan repayments as a monthly outgoing in affordability checks.
Is a longer term always better for affordability?
A longer term can increase borrowing capacity, but it may increase total interest over the life of the mortgage.
Disclaimer: Information on this page is for educational purposes only and is not financial advice. Always verify details with a qualified mortgage adviser or lender.