This article aimed to identify the usefulness of using social networking sites (SNSs) in an English as a foreign language class. One hundred sixteen undergraduate students of diverse degrees from a polytechnic state-owned university in Ecuador participated in the study, which followed a quantitative design. A descriptive analysis and a linear regression model were used to analyze the data gathered through an online survey. Results reported that participants agreed on average with all the propositions, thus confirming their perception of the usefulness of the SNSs used in class. Also, it was identified that the factors "Interaction with the teacher" (t = -0.116, p = 0.908) and "Engagement" (t = 1.508, p = 0.133) are not statistically significant predictors of student performance. Also, the factors "Interaction with peers" (t = 11.717, p < 0.001) and "Influence on cooperative learning" (t = 10.088, p < .001) were significant predictors in the model. The results of this investigation directly impact teachers' practice and students who will be the first recipients of the advantages of using this tool in class.