Engaging customers online through effective customer experience design is critical, as academics and researchers agree that engaged customers contribute value to firms. However, in the multinational business-to-business (B2B) context—due to its complex decision-making processes, which involve various stakeholders—global marketers face challenges in their attempts to localize (versus standardize) the online experience across their regional websites to meet customer needs, which vary across cultures. Although standardization entails cost benefits, localization provides more culturally relevant customer experiences. Accordingly, to help global marketers solve this dilemma, this study examines how culture shapes the effectiveness of online customer experiences with regard to driving psychological and behavioral customer engagement in a B2B context. The study draws on survey and observed data collected from the business customers of a multinational firm who were located in 79 countries to demonstrate why global marketers should finetune such experiences in accordance with between-country cultural differences. The results show that different cultural factors can enhance or hamper engagement responses to cognitive and social online customer experiences and thus have actionable practical implications for prioritizing distinct localization strategies.