You can file a dispute online, by phone or by mail. The Consumer Finance Protection Bureau offers detailed instructions on how to write your letter, including a sample letter template, and offers information for contacting Equifax, Experian and TransUnion separately, since some errors may occur on only one or two of your credit reports.  Each credit reporting agency contains similar information on its websites. Be wary of organizations that claim to "repair your credit" but want to charge a fee, since disputing an error on your credit report should be a free process provided directly by the credit reporting agency. Read more: How to Dispute an Error on Your Credit Report