Your potential mortgage provider will use one of the three credit reference agencies, Equifax, Experian and Callcredit to ascertain your credit rating. Having credit cards does not mean that you won’t be able to secure a mortgage, but your lender will want to see that you are able to manage debt responsibly. Switching to a 0% credit card enables you to pay off current debt by transferring from cards on which you pay interest, to a card which has 0% interest for a set period.