[header] How to write a letter to reduce credit card interest rates [title] Create a file that includes other offers from credit cards or balance transfer offers with lower interest rates offered. [step] If you haven't received any in the mail, or if you've thrown them all in the trash, do some research online to find other offers with lower interest rates. [title] Find out what the current prime rate is. 
[step] The federal reserve sets this as a standard for lenders and banks. Credit card companies use this to set their interest rates, usually staying within 9 percent of the prime rate.