This study aims to understand customers' preferred attributes and features of curated subscription box services (CSBS) for pet products and to segment customer groups by favored attributes and features to optimize the CSBS. First, a pretest with 46 students at a southwestern public university in the U.S. was implemented to explore customers' preferences on attributes and features in the subscription service. Choice-based conjoint (CBC) analysis was employed in the challenging tradeoff situations after MaxDiff (best-worst scaling) evaluation. Next, the main study was conducted using the survey method with 350 American pet owners recruited by the commercial data platform called Prolific. The preference of five CSBS attributes (i.e., product, personalization, e-service quality, communication and interaction, and price) and 18 related features were examined. Cluster analysis for the 350 respondents identified customer segment groups based on their CSBS preferences derived from the conjoint analysis. The results of this study support that customers prioritized price, product, and personalization attributes in their CSBS choice. The three groups are product-oriented, personalization-oriented, and price-favored segments. This study provides practical implications for understanding customers' preferences and traits and how to tailor subscription box services for the pet business and even for eCommerce subscription retailers in other product …