Background: Numerous studies have examined the impact of global budget payment systems of health insurance on patient access to medical care. In order to monitor the population’s accessibility to health services, a series of survey are often used to understand public perceptions of the health care provider. Taiwan implemented the single-payer National Health Insurance in 1995 and has been conducting a series of surveys to monitor public perception of the NHI after adopting a global budget payment system in 2002. Although telephone surveys are commonly used in obtaining public opinions on various public health issues, limitations such as higher cost and influence of interviewers do raise some concerns. Web-based surveys, one of the alternative methods, may be free from these problems. Objective: Our aim was to examine the difference of sociodemographic characteristics, satisfaction of NHI and NHI-contracted health care providers, attitude toward NHI-related issues, behavior in seeking medical advice and self-reported health status between those who completed Web-based surveys and those reached by telephone. Methods: This study compared the demographic factors of participants who took either a Web-based survey (1313 participants) or random digit dialing telephone survey (2411 participants) that contained identical questions. Results: Compared to telephone survey respondents, Web-based respondents tended to be younger (P<.001), unmarried (P<.001), non-smokers (P<.001), with a higher education (P<.001), and a higher monthly household income (P<.001) and worse self-reported health status (P=.008); however, they were less likely to report suffering from a chronic disease (P<.001). Despite these differences in background characteristics, no significant differences were observed in their answers related to the seeking of medical care or NHI-related issues. Telephone survey respondents reported greater satisfaction with NHI services. Web-based surveys were also shown to provide a lower average cost per sample (US$0.71) compared to telephone surveys (US$3.98). Conclusions: Web-based surveys provide a low-cost alternative method for the polling of public attitudes toward NHI-related issues. Despite general similarities between the two polling methods with regard to responses, respondents to telephone surveys reported a stronger agreement with regard to satisfaction with NHI services and a more positive self-reported health status.