The resulting ability to make monthly payments consistently and on time while also reducing overall debt loads is what will affect your credit score. (stockmonkeys.com)
It is also a bad idea to use balance transfer checks to make additional retail purchases increasing overall debt load. (stockmonkeys.com)
If you have a good payment history and a low overall debt load they will often work with you because they see it as an opportunity to get additional business and future interest payments. (stockmonkeys.com)