This bachelor thesis gives insight to the reader on the 4P theory’s role in a company’s social media marketing. This is a multiple case study where the authors investigated how these two companies apply 4P theory in their social media marketing. Furthermore. social media has appeared through the era of digitalization which has become a tremendous phenomenon in a company’s marketing strategies. Therefore, there is a high competition among companies in order to attract customers through their social media platforms such as Facebook, Instagram, Twitter. In this thesis it is investigated of how companies applies the 4P theory in their social media. The research question of this thesis is as follows: How does a company apply 4P in its social media platforms? In order to answer the research question of this thesis, the authors have used existing theories on digitalization, the new 4P’s and the traditional 4P’s as well as empirical data in the form of semi structured interviews. The results showed that the 4P theory has an enormous role in these companies’ marketing in social media.