In recent years, social media has proven to be a highly influential medium, significantly shaping consumer decision-making. Its growing usage has given rise to prominent individuals with large followings across various platforms—commonly known as social media influencers (SMIs)—who hold considerable sway over public opinions within specific industries. In the tourism sector, the use of SMIs to promote travel-related activities has become increasingly widespread. Today, more tourism businesses are leveraging social media and influencer partnerships to attract customers than ever before. This study focused on exploring the effect of social media influencers’ attractiveness in shaping the travel decisions of domestic tourists in Kenya. The research was grounded in two theories: The Theory of Reasoned Action and Attribution Theory. The target population included followers of social media influencers in Nairobi and Kiambu Counties of Kenya. Employing a mixed-methods approach, the study gathered data through questionnaires from 399 respondents which was then analyzed to meet the outlined objective. The findings revealed a strong influence between source attractiveness and domestic tourists’ decision-making. Drawing from the study's findings, which emphasize the strong impact of source attractiveness—especially in terms of similarity and likability—on the decision-making of domestic tourists in Kenya, several recommendations are suggested. Firstly, tourism marketers should focus on partnering with influencers who closely align with the cultural background, lifestyle, and demographic characteristics of their intended domestic audience. Secondly, those in the tourism sector should invest in influencer-driven campaigns for domestic tourism in order to effectively capitalize on the role of source attractiveness in influencing domestic tourists' decision-making processes and boost engagement in Kenya's local tourism sector.