Purpose: The purpose of this paper is to determine predictors of social network services use among college students at two Turkish universities, with particular emphasis on Facebook, Twitter, Foursquare, and Instagram. Design/methodology/approach: A written questionnaire was administered to 822 college students from various faculties. The data obtained from the corresponding questionnaire were analyzed using ordered logit analysis and four different models were independently estimated with respect to social network services. Findings: Ordered logit estimation results revealed that frequency of log in to social network sites, time spent on social network sites, and following event alerts were three predictors that had significant impact on the frequency of all four social network sites' use. Particularly; event participation, information sharing, following on top ranked topics, and purchasing a product through social media were the other additional predictors of college students' willingness to use the corresponding social network sites. Originality/value: Although a vast literature exists on the use of social network services among college students, relatively little work was published which compares several social network services and predictors of their use. This paper may contribute to the existing literature by presenting the predictors of college students' use of four different social network services in a specific area of Turkey and providing a comprehensive comparison between them.