This study aims to explore shopping usage pattern on NAVER, the top-ranked portal platform in South Korea, and to identify user segmentation based on actual behavioral purchase data. To accomplish this, we analyzed NAVER Shopping’s transaction-level behavioral data provided by NAVER Cloud, focusing on purchase activities conducted on both PC and mobile devices across various product categories. The analysis revealed three major findings. First, the presence of All-rounders shoppers indicates that consumers increasingly perceive NAVER not only as an information-seeking portal but also as an integrated commerce platform. Second, despite the dominance of mobile transactions, a distinct group of PC Shoppers continues to exist, demonstrating a holistic PC-based consumer journey that includes search, comparison, and purchase within a single portal environment. Third, five shopper clusters were identified: All-rounders, PC Shoppers, Food-focused Shoppers, Life/Health-focused Shoppers, and Baby/Nursing-focused Shoppers. Theoretically, this study contributes by integrating portal-based search behavior with commerce behavior frameworks, extending discussions on how portal platforms evolve into commerce ecosystems. Practically, the findings provide deeper insights into digital commerce patterns and offer strategic implications for platform operators and marketers seeking sustainable growth within portal-based e-commerce environments.