Internet research is appealing because it is a cost- and time-efficient way to access a large number of participants; however, the validity of Internet research for important subjective well-being (SWB) surveys has not been adequately assessed. The goal of the present study was to validate the Satisfaction With Life Scale (SWLS; Diener, Emmons, Larsen, & Griffin, 1985), the Positive and Negative Affect Schedule (PANAS-X; Watson & Clark, 1994), and the Subjective Happiness Scale (SHS; Lyubomirsky & Lepper, 1999) for use on the Internet. This study compared the quality of data collected using paper-based (paper-and-pencil version in a lab setting), computer-based (Web-based version in a lab setting), and Internet (Web-based version on a computer of the participant’s choosing) surveys for these three measures of SWB. The paper-based and computer-based experiment recruited two college student samples; the Internet experiments recruited a college student sample and an adult sample responding to ads on different social-networking Web sites. This study provides support for the reliability, validity, and generalizability of the Internet format of the SWLS, PANAS-X, and SHS. Across the three experiments, the results indicate that the computer-based and Internet surveys had means, standard deviations, reliabilities, and factor structures that were similar to those of the paper-based versions. The discussion examines the difficulty of higher attrition for the Internet version, the need to examine reverse-coded items in the future, and the possibility that unhappy individuals are more likely to participate in Internet surveys of SWB.