The number to request that your name be removed from unsolicited credit card applications is 1-888-5-OPT-OUT.
This is the number mentioned on the air by WTOP's Call for Action Director Shirley Rooker.
The information only goes to the three major credit bureaus and the information you provide is used to stop your credit history from being sold to companies that want to screen you for a credit card. The number was established by the credit bureaus to provide a quick and easy way for consumers to get their names of the pre approved credit card lists. You will not receive any written acknowledgement but you should find that these offers stop arriving in your mail box.