You can indicate on the application that you have an existing Amex account. They usually permit you to hold more than one account at a time. I've churned several credit cards over the last few years for bonus miles: Amex Aeroplanplus Gold, CIBC Aerogold, RBC Avion Visa, Amex Gold Rewards Business, Amex SPG. Applying for multiple credit cards will affect your credit score to some degree, so if you're in the market for a mortgage, don't play around with churning. I was only once denied a credit card because I had too much open credit at the time. Closing a $25 000 LoC I had no need for and reducing the limit on one credit card did the trick and I was able to successfully reapply a month later.