I have about 20 credit cards and have just applied for a new one because I was approached at a shopping center and was offering a $25 bonus. I use one credit card mainly, and the other credit cards are not used at all. Will canceling the other cards effect my credit rating? I pay the card off on time every month and have never paid any interest in the last 20 years. Which way is best for me? keep all the cards, even the ones I do not use or cancel all my cards except the one I use?