Mortgage Affordability Calculator — How Much Can You Borrow?
Find out how much you could borrow based on your income, deposit, and monthly expenses. Instant estimates tailored to UK lender criteria.
Mortgage Affordability Calculator
Calculate how much you could borrow for your dream home
👤 Primary Applicant
👥 Second Applicant
Enable to add joint application income
Your Borrowing Capacity
You could borrow between: £225,000 - £250,000
This estimate uses standard income multiples and current affordability assumptions to show your likely borrowing range.
A borrowing level near £250,000 is typically stress-tested against your outgoings, credit profile, and lender-specific affordability rules before a formal offer is made.
Important: This calculator provides estimates based on standard lending multiples. Actual lending criteria vary between lenders and depend on credit history, existing commitments, and comprehensive affordability assessments.
Get Your Free Mortgage in Principle
Ready to turn your estimate into a confirmed offer? A Mortgage in Principle (also called a Decision in Principle) shows sellers and estate agents you're a serious buyer with verified affordability.
- Confirmation of how much you can borrow
- Strengthens your position when making offers
- Valid for 60–90 days, with access to 90+ lenders
- No impact on credit score — soft search only
Your Borrowing Potential
Understanding Your Mortgage Borrowing Capacity
When planning to buy a home, the first question is usually: "How much can I borrow for a mortgage?" This calculator gives you an instant estimate based on how UK lenders assess affordability in 2026.
Your borrowing capacity depends on several key factors — and the calculator above gives you a solid starting point based on standard lending multiples. Your actual mortgage offer will depend on a full affordability assessment.
Tip: Paying down credit cards improves affordability more than saving the same amount as additional deposit — because lenders assess monthly commitments, not just deposit size.
Key factors lenders consider
Behind the Numbers
How Do Mortgage Lenders Calculate Affordability?
UK lenders use two methods — and you must pass both to get approved. Here's exactly how each works.
Income Multiples
Most lenders offer 4–4.5× your annual income. Some offer up to 5–5.5× for professionals, larger deposits, or specific products.
Affordability Assessment
Even if income multiples suggest £300k, high monthly commitments can reduce this. Lenders verify you can genuinely afford repayments by:
- → Stress testing at 3% above the quoted rate
- → Deducting all monthly commitments (credit cards, loans, childcare)
- → Reviewing living expenses against your spending or ONS data
- → Considering future changes (retirement, family plans)
What Affects Borrowing
What Affects How Much You Can Borrow?
Income Lenders Accept
- ✓ Basic salary and guaranteed overtime (100%)
- ✓ Bonuses and commission (averaged over 2–3 years)
- ✓ Self-employed profits from accounts or SA302s
- ✓ Rental income from existing properties (75–80%)
- ✓ Contractor day rates (specialist assessment)
Commitments That Reduce Borrowing
- → Credit cards (assessed at 3–5% of balance monthly)
- → Personal loans, car finance, student loans
- → Childcare costs and maintenance payments
- → Service charges and ground rent
Deposit Impact on Rates
- 5% Minimum for first-time buyers
- 10-15% Better rates and wider product choice
- 20%+ Best rates and lowest fees
- 25%+ Required for buy-to-let mortgages
After the Calculator
What to Do After Using This Calculator
Calculate Your Monthly Payments
Use our Monthly Payment Calculator to see what your borrowing would cost per month at current mortgage rates — and compare different term lengths.
Go to Monthly Payment Calculator →Calculate Your Stamp Duty
Use our Stamp Duty Calculator to work out total purchase costs including the tax — including first-time buyer relief and additional property surcharges.
Go to Stamp Duty Calculator →Get Expert Mortgage Advice
Calculators provide estimates. Our advisers access 90+ UK lenders, often find higher borrowing through detailed assessments, and provide specialist guidance for complex cases.
Book a free consultation →Improve Your Affordability
Before applying: pay down credit cards and close unused accounts, register to vote, save a larger deposit, and gather income documentation — payslips, SA302s, bank statements.
Common Questions
Mortgage Affordability FAQs
How much can I borrow for a mortgage?
How do lenders calculate mortgage affordability?
Can I borrow more with a joint mortgage?
Does my deposit affect how much I can borrow?
How accurate is this affordability calculator?
Can I borrow more than 4.5 times my salary?
Can self-employed people get mortgages?
What if I have bad credit?
Get a Personalised Affordability Assessment
Calculators provide useful estimates, but every situation is unique. Our advisers often find higher borrowing offers through detailed assessments and access to lenders not available on comparison sites.
Or call us on 01628 884 693