Millions of Britons could see their credit ratings compromised without knowing it, simply because of the actions of an ex-spouse, says online credit report service Credit Expert.

According to the recent report, more than half of those surveyed did not know that the financial status of an ex-spouse or ex-partner can have a negative effect on their credit rating. It was also reported that one in ten Britons currently in a relationship and sharing finances admit keeping a bank account secret from their partner, while one in five hide their debt and money worries from their partner. This amounts to some £30 billion of ‘hidden' debt.

A previous report from insurance firm Aviva shows that £4.3 billion is spent annually in the UK on divorce settlements and that 62 per cent of couples share their finances prior to the split. This does not include the many millions of unmarried couples for whom separation is equally, if not more, financially challenging.

"Action should be taken by those who have shared accounts during a relationship to prevent their ex-partner's bad habits from having a negative impact on their own credit rating," says Nigel Spicer. "Just applying for a credit account in joint names can link two individuals for a long time, even if the account is not opened."

Other findings from the Credit Expert report include:

• 50 per cent of those surveyed wrongly believe that the financial status of previous occupants of their home can affect their credit rating, while 56 per cent think that the poor credit history of other family members can do so. This is only true if they are linked to you financially;
• 75 per cent wrongly think that a bad credit history puts you on a credit blacklist. These do not exist. No matter how bad your credit rating is, you will not be placed on a blacklist;
• 50 per cent do not know that being registered to vote will improve their credit rating;
• 48 per cent do not know that checking their credit report will not affect their credit rating;
• 48 per cent do not know that paying a mobile phone bill late will impair their credit rating;
• Nine out of ten do not realise that being turned down for credit will not show up on their credit report. Any application for credit will show up, however, and numerous applications (accepted or declined) will have a negative impact on someone's credit rating; and
• 80 per cent do not know that the size of their credit limit can also affect their credit rating.

With recent reports indicating that lending criteria are set to become more conservative, the wisdom of looking after your credit rating is obvious.