Despite the popularity of online auctions as a new e-commerce operating model, few studies have explored why sellers intend to pay for the services of particular auction sites, especially while other free auction services exist. Developed on the basis of the theory of perceived value, this study includes network externalities in seller perceptions and explores why sellers intend to pay for these services. This study employed structural equation modeling (SEM) to investigate a research model based on a survey of 336 online sellers. The results show that perceived network externalities affecting sellers’ intention to pay are composed of perceived benefits (usefulness and social benefit), perceived costs (searching cost, monitoring cost, and adapting cost), and perceived value of selling through the website auction. Another valuable finding was that expert sellers and non-expert sellers differ in their perceptions of the value of online auctions. The implications of these findings are discussed.