Experian vs Equifax vs TransUnion: The UK's Three Credit Agencies Explained

If you've ever checked your credit score in two different places and got two wildly different numbers, you're not imagining it. The UK has three credit reference agencies, each one runs its own scale, and each one holds slightly different data on you. Confused? Reasonable. Here's everything you need to know.

Why are there three credit agencies?

The short answer is competition. Credit reference agencies are private companies that sit between lenders (who report data) and other lenders (who use that data to decide whether to lend). Having three of them keeps prices competitive and means no single company has total control over the data that affects whether you can get a credit card or a mortgage.

The slightly longer answer is that each agency has built its own data set over time. Lenders aren't required to report to all three — some only report to one or two. So your file at Experian might show a loan that's missing from TransUnion, and vice versa. Three agencies means three versions of "you" — usually similar, occasionally different in ways that matter.

If you're brand new to credit files in general, the credit score introduction guide covers the basics first.

What does each agency do?

Each agency does broadly the same thing: collects data on UK borrowers, packages it into a credit file, gives you a score, and sells access to lenders making credit decisions. But their data sources and their scoring models are subtly different — which is why the same person can look slightly different on each file.

What's on every file:

• Your name, date of birth and current address
• Address history (usually six years)
• Credit accounts: cards, loans, mortgages, finance agreements
• Payment history on each account
• Public records: CCJs, IVAs, bankruptcies
• Hard searches from the last 12 months
• Electoral roll status

None of these files contain your salary, savings, ethnicity, marital status or political views. They're purely about credit history.

Experian explained

Experian is the largest of the three credit reference agencies in the UK, both in market share and in name recognition. Their scoring scale runs from 0 to 999, divided into bands:

• 0–560: Very poor
• 561–720: Poor
• 721–880: Fair
• 881–960: Good
• 961–999: Excellent

(Experian sometimes adjusts these bands slightly, so the figures here are indicative.)

Experian is the agency most used by mainstream high-street lenders, especially for mortgages. If you're planning a big credit application, your Experian file is probably the one to focus on first. You can check your Experian score for free at experian.co.uk — our free credit check guide walks through the sign-up.

Equifax explained

Equifax is the second-largest in the UK, and is the agency behind ClearScore — the free service most people in the UK use to check their credit. Their scale runs 0 to 1,000:

• 0–379: Very poor
• 380–419: Poor
• 420–465: Fair
• 466–700: Good
• 701–1,000: Excellent

Equifax data is widely used in credit card decisions and personal loan applications. Many lenders that don't use Experian will use Equifax instead — so a clean Equifax file is just as important as a clean Experian one if your application is being processed by an Equifax-using lender.

The easiest way to see your Equifax data is through ClearScore (clearscore.com), which is free for life and updates monthly.

TransUnion explained

TransUnion is the smallest of the three but still significant, and is the agency behind Credit Karma. Their scale is the most compact:

• 0–550: Very poor
• 551–565: Poor
• 566–603: Fair
• 604–627: Good
• 628–710: Excellent

Yes — the maximum is 710, much lower than the other two. So if your TransUnion score is 600 and your Experian is 920, your file isn't worse on TransUnion. They're just measuring on a smaller ruler.

Some lenders rely on TransUnion as their primary source. Others use it as a secondary check alongside Experian or Equifax. You can check your TransUnion data for free via Credit Karma (creditkarma.co.uk).

How do their scoring scales compare?

Side-by-side, the differences look stark:

• Experian: 0–999, "good" starts around 881
• Equifax: 0–1,000, "good" starts around 466
• TransUnion: 0–710, "good" starts around 604

That's why direct comparison of the raw numbers is meaningless. The trick is to look at the band each agency puts you in. If all three say "good", you're in a similar place at all three. If one says "fair" and two say "good", something is reporting differently on the "fair" file — worth digging into.

Why your score differs between agencies

There are three main reasons your score can be noticeably different at different agencies:

1. Different data. Not every lender reports to all three agencies. A loan that's pulling your file down might only show up on two of them.
2. Different scoring models. Each agency weighs factors slightly differently. Equifax might penalise high utilisation more heavily than Experian, for example.
3. Different scales. As above — the raw numbers aren't comparable.

If you find a big discrepancy in the band (e.g. excellent at Experian but fair at TransUnion), the most likely explanation is missing or incorrect data on one file. That's worth checking with the dispute process — and our guide to improving your score covers what to look for.

Which agency do lenders use?

It varies wildly. Some lenders only check one agency. Some check all three. Some run blended models that combine data from two or more. Many don't publish which agency they use — partly because they want flexibility, partly because they don't want applicants gaming the system.

Some loose patterns:

• Major high-street banks often start with Experian
• Mortgage lenders frequently use Experian or Equifax (sometimes both)
• Credit card issuers commonly use Equifax
• Specialist and online lenders are more likely to use TransUnion

But every lender has its own rules, and these patterns shift. The honest, practical answer is: you can't predict which agency will be used for any given application, so all three matter.

Should you check all three?

Yes. Especially if you're planning a big application.

It costs you nothing — all three free services (Experian, ClearScore, Credit Karma) are free for life. It takes about 30 minutes in total to sign up to all three. And it shows you any inconsistencies between the files: an account that's been correctly reported to two agencies but not the third, an old address that's lingering on one file but cleared from the others, a mistake that only one agency has been told to fix.

The full picture is the only picture that matches what a lender might actually see.

How to get your free reports

Here's the quick rundown:

• Experian: experian.co.uk → "Free credit score" (avoid the CreditExpert paid trial)
• Equifax: via clearscore.com (the easiest way to see your Equifax data for free)
• TransUnion: via creditkarma.co.uk (free for life)

Sign-up at each takes about ten minutes — they verify your identity by asking questions about your credit history. After that you can log in whenever you want. None of it affects your score.

Once you've got the full picture, you can start working on whatever needs fixing. Our credit score improvement guide walks through the practical steps in order of impact.

Frequently asked questions