The digital transformation era has profoundly altered how small and medium-sized enterprises (SMEs) compete, particularly those in traditional industries. This study examines the relationship between second-order digital marketing and purchase intention, emphasizing the mediating role of e-service quality in Ulos-based SMEs in North Sumatra, Indonesia. Digital marketing is conceptualized as a second-order construct composed of cost efficiency, incentive programs, interactivity, and site design, reflecting the multidimensional nature of digital strategies. Data were collected from customers of Ulos SMEs who had engaged with online platforms through a structured survey. The measurement and structural models were tested using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results confirm that digital marketing significantly affects its four dimensions and positively predicts e-service quality. However, the direct effect of digital marketing on purchase intention was insignificant. Instead, e-service quality strongly affects purchase intention and mediates the relationship between digital marketing and purchase intention. The model explained 54.6% of the variance in e-service quality and 65.9% in purchase intention, indicating substantial explanatory power. The findings contribute theoretically by validating digital marketing as a second-order construct and clarifying the mediating role of e-service quality, thereby addressing prior inconsistencies in the literature. Practically, the results underscore that SMEs, particularly in cultural industries such as Ulos, must integrate service quality with digital marketing to convert exposure into purchase behavior. This study highlights how balancing cultural authenticity with digital innovation enables heritage-based SMEs to achieve sustainability and competitiveness in the digital economy.