In recent years, there has been a significant growth in the number of online transactions. Consumers are increasingly using social media platforms to make purchases, which raises the question of whether there is a difference between purchases made through social media and those made from e-commerce sites. The purpose of this research paper is to investigate the influence of consumers' expectations from social media and e-commerce platforms service quality on their satisfaction, seeking for the future improvement in a corporate purchasing environment. The study was conducted according to the original SERVQUAL method. The questionnaire administrated comprised of the four out of five original SERVQUAL dimensions, namely responsiveness-reliability-assurance-empathy, while tangibles dimension was replaced with perceived value (P.V.), to more appropriately reflect the online environment. Six hypotheses were formulated, and data were analyzed through IBM SPSS version 19. Regression analysis for both environments was performed to test the first five hypotheses, and Laplace criterion was chosen, as a decision theory selection criterion to test the last one. It was proved that that for customers of both social media and e-commerce platforms and purchasing environments, perceived value (P.V.) was the most important feature, followed by assurance, responsiveness, and last reliability. It was also showed that there is actually a different level of expectations between the two purchasing environments, where consumers seem to expect more from e-commerce platforms purchasing environments than social media ones.