You have a statutory right to a copy of your credit file from each of the three UK credit reference agencies. Most people use free consumer services: MoneySavingExpert's Credit Club (Experian), ClearScore (Equifax) and Credit Karma (TransUnion).
Check for common problems: old addresses still linked to your file, financial associations with ex-partners, accounts that should be closed, and any account or default you don't recognise. Any of these can drag down a score.
To correct an error, raise a Notice of Dispute with the credit reference agency. They must investigate with the lender. If that doesn't resolve it you can add a Notice of Correction — a short statement lenders see when reviewing your file.
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Credit Files & Scores
Correcting mistakes on your credit file
You have a legal right to have inaccurate information corrected — for free.
ReadDefaults & Missed Payments
What a default really is — and when one can be registered
A default is a formal statement that an account has broken down. There are rules about when it can be recorded.
ReadDefaults & Missed Payments
How long defaults affect you — and how to move on
Defaults stay on your credit file for six years from the default date, whether or not the debt is cleared.
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