Experian vs Equifax vs TransUnion

The UK has three credit reference agencies (CRAs): Experian, Equifax and TransUnion. If you have ever checked your credit score on more than one site and seen different numbers, that is why. Each agency holds its own data, applies its own scoring model, and produces its own score. For example, you might check Credit Karma UK on a Monday and see a TransUnion score of 480, then check ClearScore on Wednesday and see an Equifax score of 390 for the same week, same person, same financial behaviour, two very different-looking numbers.

This article provides general information about credit reference agencies in the UK. It is not personal financial advice. Your individual circumstances will vary, and a useful first step is to check your own credit files directly with each agency.

How do the three agencies compare?

All three agencies are authorised by the Financial Conduct Authority (FCA) and regulated under UK data protection law. They collect information about how people manage credit and sell that data, in a controlled way, to lenders, landlords and other authorised parties.

The key differences lie in the scoring scales they use, the lenders that report to them, and the consumer-facing products they offer. The table below summarises the main points of comparison.

Scoring scale URLs last verified June 2025. The "Good" thresholds are each agency's own published guides, are approximate, and may change over time. Verify current thresholds directly with each agency.

Why do scores differ between agencies?

The scores differ for two main reasons: different underlying data, and different scoring formulas.

Different data. Not every lender reports to every agency. A credit card provider might report your repayment history to Experian and TransUnion but not to Equifax. A mobile phone contract might only be visible at one agency. If a positive account appears at two agencies but not the third, your score at that third agency may look lower, even though your actual behaviour is the same.

Different scoring models. Even if two agencies held identical data, they would likely produce different scores. Each agency has its own algorithm: the weighting given to missed payments, the impact of a county court judgement (CCJ), how much credit utilisation is considered high, and how long past negatives take to fade. These formulas are not published in detail.

This is why comparing scores between agencies as if they were the same number is misleading. A score of 650 at TransUnion is not the same as a score of 650 at Experian. They sit on different scales and represent different assessments.

A real-world illustration. Consider a hypothetical borrower, call her Sarah, who applies for a car finance agreement. The lender queries only TransUnion. Sarah's TransUnion file is missing a three-year-old credit card account that she has managed well, because that card provider reports only to Experian and Equifax. Without that positive history, her TransUnion score looks thinner than her other two files, and the lender's automated system flags her as higher risk. The application is referred for manual review rather than approved instantly. Sarah's actual payment behaviour has not changed; the gap is purely a data-reporting one. Checking all three files before applying would have shown her where the discrepancy lay.

What information does each agency hold?

Despite the differences above, all three agencies collect broadly the same categories of information:

• Payment history: whether you have paid bills and loan instalments on time.
• Credit accounts: the type, age and current balance of your open and closed credit accounts.
• Credit searches: hard searches (formal credit applications) and soft searches (eligibility checks or your own enquiries).
• Public records: CCJs, insolvency orders (including individual voluntary arrangements and debt relief orders), and bankruptcy.
• Electoral roll: whether you appear on the electoral roll at your current address.
• Linked addresses and financial associations: past addresses and joint financial products.

Information typically stays on your file for six years, though the exact rules vary by entry type.

Which agency does my lender use?

There is no single answer to this. Lenders decide for themselves which agency or agencies they query. Many use more than one. Some use all three.

Because lenders do not publish which agencies they rely on, you cannot predict in advance whether a particular lender will see your Experian file, your TransUnion file, both, or all three. A lender's privacy notice sometimes names the agencies it uses, and it can be worth checking before you apply. For example, a mortgage lender's privacy notice might include a sentence such as: "We may share your personal data with credit reference agencies including Experian, Equifax and TransUnion, who will record details of any searches and accounts." A personal loan provider's notice might list only one or two agencies by name. These notices are usually found under a "Privacy Policy" or "How we use your data" link on the lender's website, or in the pre-contractual information pack.

This has a practical implication: if one of your credit files contains an error, a lender querying that file may see inaccurate information even if your other two files are clean. Checking all three files, not just the one attached to the free service you happen to use, is the more complete picture.

Which suits whom?

Different people will find different agencies most useful depending on their situation.

If you mainly want a free ongoing score: ClearScore (Equifax data) and Credit Karma UK (TransUnion data) both offer free ongoing access with regular updates. Experian's free tier offers report access; a live score is available on the paid tier or sometimes via the Experian app.

If you are preparing to apply for a mortgage or large loan: Checking all three files before you apply is worth considering. Errors at any agency could affect a decision if that lender queries that agency. Statutory reports from all three cost nothing and give you a full snapshot.

If you have noticed a discrepancy: If a score at one agency looks significantly lower, check the underlying report, not just the score, to understand why. Look for accounts you do not recognise, incorrect personal details, or entries that should have dropped off after six years.

If you are working on rebuilding credit: Positive actions tend to flow through to all three agencies over time, because most mainstream lenders report to more than one. However, the timing of updates varies. It can help to check all three files periodically rather than relying on one number as a proxy for all. For more on steps that may help over time, see our guide to credit rebuilding and bad credit options.

What to check on each of your three files

Even if your overall scores look similar, it is worth reviewing the detail at each agency. The scenario described earlier, where a positive account appears at two agencies but not the third, is exactly the kind of discrepancy that a file-by-file check can reveal:

1. Personal details: name, date of birth and address history. Errors here can affect matching accuracy and may explain why an account appears at one agency but not another.
2. Electoral roll entry: being registered at your current address is one of the simpler things that helps your score across all agencies.
3. Open accounts: confirm you recognise every account listed at each agency separately. An account present at two agencies but absent from the third may indicate a reporting gap rather than fraud, but it is worth querying either way.
4. Closed accounts: check that old accounts are marked as closed and settled correctly at each agency, as closure dates can differ between files.
5. Missed payments and defaults: confirm the dates and amounts are accurate. If an entry is more than six years old, it should not appear.
6. Hard searches: if you see searches you did not initiate, query them with the agency directly. A search appearing at one agency but not the others can sometimes indicate a data-routing issue.

If you find an error, contact the agency. Each agency has a dispute process. You can also contact the lender that supplied the incorrect data. The agency is required to investigate and correct genuine errors.

Frequently asked questions

Why is my Experian score different from my Equifax score? Each agency uses its own scoring scale and holds data from different lenders. Not all lenders report to all three agencies, so the underlying information can vary. A different score does not mean one agency is wrong, it reflects different data and a different calculation.

Which credit reference agency do lenders use? Lenders choose which agency or agencies they check. Many use more than one. You cannot know in advance which agencies a specific lender queries without asking them directly or checking the lender's privacy notice.

How do I check my credit report for free? You are entitled to a free statutory credit report from each agency under UK data protection law. Experian, Equifax and TransUnion all offer free online access. Free access may show your report without a real-time score; paid tiers typically add ongoing score tracking.

Does checking my own credit report affect my score? No. Checking your own report is a soft search and leaves no mark visible to lenders. Only hard searches, carried out when you formally apply for credit, can affect your score.

Should I worry if one agency shows a lower score? A lower score at one agency is worth investigating. Check that agency's report for errors, unfamiliar accounts, or outdated negative entries. If you find a mistake, you can raise a dispute directly with that agency. One lower score does not automatically mean a lender will decline you.

Can I improve my score with all three agencies at once? Positive habits, paying on time, keeping credit utilisation low, and staying on the electoral roll are reported by most lenders to most agencies and tend to lift scores across all three over time. The pace and scale of improvement will vary between agencies.

Sources and further reading

For the most up-to-date information on scoring scales, free access options, and dispute processes, visit each agency directly:

• Experian UK: www.experian.co.uk/consumer/guides/good-credit-score.html
• Equifax UK: www.equifax.co.uk/resources/credit-score/what-is-a-good-credit-score.html
• TransUnion UK: www.transunion.co.uk/consumer/credit-score

For the parent guide to credit reports and scores, see the credit reports and scores guide.

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