Customer loyalty is a key driver of financial performance in service organizations. We investigate whether or not online customer loyalty can be increased through enhancing the perceived service quality, reducing perceived sacrifice and improving the perceived service outcome in the online service context with the possible availability of live help service technology. We also investigate the moderating role of customer product knowledge on these relationships. The empirical results indicate that 1) online customer loyalty increases with higher perceived service quality, lower perceived sacrifice and better perceived service outcome, 2) perceived service quality positively influences perceived service outcome while perceived sacrifice negatively influences perceived service outcome, 3) customer product knowledge negatively moderates the relationship between perceived service quality and online customer loyalty such that greater product knowledge weakens that relationship, 4) customer product knowledge positively moderates the relationship between perceived sacrifice and online customer loyalty. Theoretical and practical implications are discussed.