During 2004, the IC3 Web site received 207,449 complaints regarding fraudulent and non-fraudulent interactions through the Internet, a 66.6-percent increase over 2003. IC3 referred 190,143 of these complaints to enforcement agencies. Of these, 103,959 were complaints of fraud, the majority of which were committed over the Internet or similar online service, a 64.2-percent increase over the 2003 referrals. The dollar loss from all referred cases of fraud was $68.14 million, with a median dollar loss of $219.56 per complaint. Internet auction fraud was the most reported offense, composing 71.2 percent of referred complaints. Undelivered merchandise and/or payment accounted for 15.8 percent of complaints, and credit/debit card fraud was involved in 5.4 percent of complaints. The highest median dollar losses were from check fraud ($3,600), Nigerian letter fraud ($3,000), and confidence fraud ($1,000). Among known perpetrators, 74.7 percent were male, and half lived in one of six U.S. States. Among complainants, 67.2 percent were male, nearly half were between 30 and 50 years old, and over one-third lived in one of the four most populated States. Males lost more money than females, possibly due to gender differences in patterns of online purchasing and type of fraud schemes. E-mail and Web pages were the two primary mechanisms by which the fraud was perpetrated, with 63.5 percent reporting contact with the perpetrator via e-mail and 23.5 percent having contact through a Web page. 5 tables, 7 charts, and appended information on Internet fraud schemes, complainant/perpetrator statistics by State, and tips for preventing Internet fraud