The company also stated that people should review their credit cards every year as the industry does not "reward loyalty", as the best deals are usually limited to new customers.
David Black, the principal consultant for banking at Defaqto, said: "Credit is getting harder to obtain nowadays but this should not deter existing customers from checking that their credit card still offers the best deal.
"The market is awash with introductory offers and if you have a good credit rating then it's likely that you could find a better offer elsewhere."
Earlier this year, Defaqto also urged people to use different cards for different types of spend, as doing so they can benefit from different rewards such as air miles and points schemes.
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