Why Your Experian, Equifax and TransUnion Scores Never Match

Check your credit score on three different apps and you'll almost certainly get three different numbers. It happens so consistently that it's one of the most common questions in UK personal finance — and it's not a bug, a glitch, or anyone's fault. It's how the system is built.

There isn't one UK credit score — there are three separate files

Experian, Equifax and TransUnion are three independent, competing companies. Each one collects data from its own panel of lenders, and not every lender reports to all three. A credit card provider might report to Experian and Equifax but not TransUnion. A mobile phone contract might only report to one. The result is that each bureau builds its own version of your credit history, from a slightly different set of raw data.

On top of that, each bureau uses its own scoring model, with its own scale — Experian's score runs 0–999, Equifax's runs 0–1000, and TransUnion's runs 0–710. The same underlying financial behaviour can produce genuinely different numbers on each scale, even before you factor in the data differences.

So which score is "the real one"?

None of them, and all of them. There's no single master file that lenders universally consult. When you apply for credit, the lender chooses which bureau (or bureaus) to check — often based on which one they have a commercial relationship with, sometimes checking more than one. This means the same application could be assessed against completely different underlying data depending on who you apply with.

This is exactly why checking only one app and assuming your file is "clean" is a risk: an error sitting on your TransUnion file could be invisible to you for years if you've only ever used an Experian-based app to check your score — see five real ways a credit report can be wrong without you ever noticing.

What this actually means for you

• Check all three, not just one. Free tools exist for each — MSE Credit Club (Experian), ClearScore (Equifax) and Credit Karma (TransUnion) are common UK options, and each bureau must also give you access to the data it holds on you.
• Fix errors on all three, separately. Disputing an inaccuracy with one bureau doesn't automatically correct the others — each is a separate legal entity holding separate data.
• Don't panic over one low number. If two out of three look strong and one looks weak, that's often a sign of a specific, fixable data gap on that one file — not evidence that your overall credit is bad.

The goal isn't chasing one "good" number. It's making sure all three tell an accurate story, since you don't get to choose which one a lender checks.