Your Money

Credit Scores — How They Work and How to Build One

A good credit score opens doors. A bad one closes them quietly, for years.

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Figures reflect UK data as of 2026. Always verify specifics before making financial decisions.

Your credit score is a number that tells lenders how risky it is to lend to you. It is calculated from your credit history — how you have managed debt in the past. Most 18-year-olds have no credit history at all, which makes them effectively invisible to lenders. That invisibility has consequences.

What a Credit Score Actually Is

There is no single universal credit score. Each of the three main UK credit reference agencies — Experian, Equifax, and TransUnion — calculates its own score using its own scale. Experian scores run from 0 to 999. Equifax uses 0 to 710. TransUnion runs 0 to 700. Lenders may use any combination of these when assessing your application.

The score reflects your credit history: whether you have borrowed before, whether you have repaid on time, how much credit you are using relative to your limit, and how long you have had credit accounts. If you have never had any credit, your file is thin — and a thin file is treated as a risk.

Why It Matters

A credit score is checked when you apply for a mobile phone contract, when you want to rent a flat (many landlords run credit checks), when you apply for a credit card, and when you want car finance or eventually a mortgage. A poor score does not just mean rejection — it means higher interest rates when you are accepted. Over a 25-year mortgage, that difference compounds into tens of thousands of pounds.

What Improves Your Score

• Paying bills on time, every time
• Being on the electoral roll (registering to vote)
• Keeping credit utilisation below 30% — if you have a £1,000 limit, keep the balance below £300
• Having a long credit history
• Having a mix of credit types (credit card, mobile contract, etc.)

What Damages Your Score

• Missed payments
• Defaults (when a lender formally records that you have failed to repay)
• County Court Judgements (CCJs)
• Applying for lots of credit in a short period — each application leaves a "hard search" on your file
• Closing old accounts (removes history from your file)
• Not being on the electoral roll

How to Build a Credit Score from Scratch

This is the common problem for 18-year-olds who have no credit history — they are "invisible" to lenders. Here is how to become visible, responsibly.

1. Register to vote. Adding yourself to the electoral roll is one of the fastest wins and takes minutes online.
2. Get a credit builder card. Cards like Aqua, Capital One Classic, or Marbles are designed for people with limited history. Use it for small purchases — petrol, a weekly shop — and pay the full balance every month. Never carry a balance.
3. Set up direct debits for all bills so you never accidentally miss a payment.
4. Never apply for multiple cards at once. Each application triggers a hard search which temporarily lowers your score.
5. Check your report regularly for errors — mistakes do happen and you can dispute them. Free checks via Experian, ClearScore (Equifax data), and Credit Karma (TransUnion data).

Common Myths

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