Declined over your overdraft.

Why this one blindsides people

An overdraft is a credit facility you were given, and using it breaks no rules. You can sit in it for years without a single adverse entry appearing on your credit file — which is why people in this position check their report, find it spotless, and cannot work out what happened.

The answer is that the credit file is only half of it. Somewhere in the process an underwriter reads your actual bank statements, usually three months of them, and forms a view about how the account is run. Your limit and balance do show on your credit file; how the account is run shows only on the statements, and the underwriter's view of that is recorded nowhere you can check.

What an underwriter is actually looking at

Whether the balance ever goes positive. An account that dips into an arranged overdraft and recovers each month reads very differently from one that never comes back out. The second suggests the overdraft has become part of normal spending rather than a buffer.

Unarranged borrowing and the charges for it. Going beyond the arranged limit is read more seriously than using it, because it suggests the money ran out before the month did. The associated fees compound the impression.

Returned direct debits. A payment attempted and bounced is the single item that carries most weight here, because it is a commitment that could not be met on the day. One is explainable; a pattern is not.

What the overdraft is funding. Statements show where the money goes. Regular gambling transactions, several buy-now-pay-later commitments or short-term lending alongside overdraft use turn one concern into a picture.

What actually fixes it

Time, and less of it than you would think. Most of this is assessed over roughly three months, so three clean statement periods genuinely change what an underwriter sees — unlike credit file entries, which sit there for six years regardless of what you do.

• Get the account back to a positive balance before each month ends, even if only just.
• Move direct debit dates to just after payday, so nothing is ever attempted against an empty account.
• Reduce the arranged limit once you are clear of it. A large unused overdraft is also a commitment some lenders count against your borrowing.
• Do not open anything new in the meantime, and do not reapply during the three months.

That is often the whole intervention. It is also the reason it is worth asking before applying again rather than after — three months of deliberate tidying is cheaper than another hard search on your file.

And if waiting is not realistic

Sometimes the timing is fixed: a purchase is in progress, or a fixed rate is ending. Lenders differ in how much weight they put on statement conduct versus the credit file, and some are considerably more interested in the overall picture than the worst month in it. Which lender your case goes to matters more here than almost anywhere else.