Existing credit card customers are of great value to credit issuers, and that will never change. In fact, some analysts estimate it costs credit card companies more than $200 to acquire a new customer. Therefore, once they have you, they really don't want to lose you. So if you are unhappy with your current interest rate, the best thing to do is simply pick up the phone, call the number on the back of your credit card, and tell them what you want. You may be surprised how easy it really is.
Before you make the call, take a few minutes to review low-interest credit card offers that are available to you. Then as you speak with the customer service representative, tell them you are receiving offers for lower rates and you would like them to match the offers. This is the most effective negotiation technique. If you don't get the answer you like the first time, hang up and call back 15 minutes later. It may take a little persistence on your part, but the end result will be well worth the extra effort.