What Is a Credit Score?
A credit score is a three-digit number (typically 300–850) that represents your creditworthiness. It's calculated from your credit history: payment patterns, credit usage, length of credit, and credit mix. In the UK, credit agencies like Experian, Equifax, and TransUnion maintain credit files that lenders use to assess mortgage risk.
Important: Every lender has their own credit scoring criteria. A score that gets you approved at one bank may not at another. Your score is a guide, not a definitive barrier.
Credit Score Ranges (UK)
While scores vary by credit agency, here's a general guide:
Excellent (750–850)
Best mortgage rates available. Lenders compete for your business. Approval is very likely.
Good (650–749)
Competitive mortgage rates. Good approval odds. You're in the majority of homebuyers.
Fair (550–649)
You can still get a mortgage, but rates may be 0.5–1% higher. Fewer lenders may accept you. Larger deposit often required.
Poor (Below 550)
Mortgage approval is difficult. Specialist lenders may help, but rates are significantly higher. Focus on improving your score before applying.
How Lenders Use Your Credit Score
Mortgage lenders don't rely on credit score alone—it's one piece of the puzzle. They also assess:
- Your deposit size and savings history
- Your income stability and affordability (LTI ratio)
- Your employment history and job security
- Details in your credit file (missed payments, defaults, county court judgments)
- Your existing debt obligations
Key Point
A 750+ score won't guarantee a mortgage if your income can't support the payments. Similarly, if you have a good income but poor credit, you may face rejection or higher rates despite strong affordability metrics.
What Damages Your Credit Score
Understanding what hurts your score helps you avoid mistakes:
Late Payments: Missing or late payments are the biggest credit killer. A single missed payment can drop your score by 100+ points. Negative markers stay on your file for 6 years.
High Credit Utilization: Using 80%+ of your credit limit signals financial stress. Aim to use less than 30% of available credit.
Too Many Hard Inquiries: Each mortgage application triggers a hard inquiry on your credit file. Multiple inquiries in a short time signal desperation and can drop your score. Space applications 2–3 weeks apart.
Defaults and CCJs: County Court Judgments (CCJs) and defaults are serious marks. They significantly lower your score and stay visible for 6 years (CCJs) or longer.
Not on Electoral Register: Missing from the electoral register makes you harder to verify. Register to vote at your current address immediately.
How to Improve Your Credit Score
If your score is below 650, focus on these improvements before applying for a mortgage:
Timeline: 6-12 Months
- Check your credit file for errors and dispute them
- Register on the electoral register
- Pay all bills and credit on time—set up automatic payments
- Reduce credit utilization to under 30%
- Don't close old credit accounts (age of credit matters)
Longer-Term (12+ Months)
- Build positive credit history with responsible borrowing
- Maintain a credit mix (credit cards, personal loans, overdrafts)
- Wait for old negative marks to age off your file
- Rebuild after defaults or CCJs (markers stay 6 years)
Free Credit Check: Check your credit file for free at Experian, Equifax, or TransUnion using their free trial services. Look for errors that you can dispute.
Credit Score and Interest Rates
The relationship between credit and rates is direct. In 2026:
- Excellent credit (750+): May get rates at 4.5%–5.0%
- Good credit (650–749): Typical rates around 5.0%–5.5%
- Fair credit (550–649): May pay 5.5%–6.5%
- Poor credit (below 550): Specialist lenders may charge 6.5%–8%+
Impact on Affordability
A 1% rate difference might seem small, but on a £200,000 mortgage over 25 years, it costs an extra £28,000+ in interest. Improving your credit score by 100 points could save you tens of thousands.
Credit Score and Deposit Size
Lenders often require larger deposits from borrowers with weaker credit. A 750+ score might get approval with a 10% deposit; a 600 score might need 15–20%. Saving a larger deposit can offset credit concerns.
Strategy: If your credit needs work, consider delaying your mortgage application 6–12 months to build your score and deposit simultaneously.
Before You Apply
Take these steps 3–6 months before applying for a mortgage:
- Check your credit file at all three agencies (Experian, Equifax, TransUnion)
- Dispute any errors immediately
- Ensure you're on the electoral register
- Pay all bills on time for at least 3 months
- Reduce credit card balances to under 30% of limits
- Avoid applying for new credit or making hard inquiries
- Don't close old credit accounts
- Use a mortgage broker (they may have access to specialist lenders who accept lower scores)