The advent of electronic commerce has revolutionised the way consumers purchase products and services. Online businesses are growing rapidly to tap into the potential demand of market consumers. Nevertheless, the full potential of business-to-consumer (B2C) e-commerce may not be fully realised with many consumers expressing reservations about engaging in e-commerce transactions. Concerns over privacy and security issues continue to steer consumers away from making Internet purchases. This has caused consumers to lose trust in online businesses. Consumers' lack of trust in online transactions has created a need for web assurance services to bridge the trust gap and re-establish consumers' faith in online businesses. This study examines whether web assurance services are effective as trust-building mechanisms which encourage consumers to engage in e-commerce transactions. In general, web assurance is a third party service that provides reasonable assurance that a web site displaying a seal of assurance is trustworthy; safe and reliable. The presence of such a seal should help create a greater perception of trust and facilitate consumers' willingness to purchase online. Web assurance services offer accounting firms an opportunity to expand their range of services at a time when markets for their traditional assurance services, such as financial statement audits, offer limited growth and high competition. This study examines the impact of the involvement of the accounting profession in the web assurance services. Accountants have no statutory monopoly over the provision of web assurance services, but may have an advantage over other competitors by offering a broader, more comprehensive service. Further, their long-standing reputation of integrity and objectivity along with their rich education and experience may make them an appealing provider of web assurance services. This study examines whether an accountant's seal, i.e., WebTrust, would create a greater perception of trust in the eyes of consumers than one produced by another seal provider, i.e., TRUSTe, and thus be more likely to lead to an intention to purchase a product online. This research contributes to the existing literature on electronic commerce assurance services by incorporating trust into the equation. The results of this research can be beneficial for the accounting profession by identifying their role in this relatively new non-traditional assurance market. The results of this study showed that web assurance had no impact on the perceived trustworthiness of a web site, regardless of the identity of the seal provider. No differences in perceived trustworthiness were found for the two different seal providers (WebTrust vs. TRUSTe) examined in this study. The results also show that the level of knowledge of Chartered Accountants did not contribute to greater perceived trust even when subjects viewed web sites with a seal of assurance provided by an accountant. Finally, overall perceived trustworthiness of a web site is found to be a key factor in influencing consumers' willingness to purchase online.