In this study, the authors analyse how teachers use different social networks and if there are differences according to sex, age and level of education they teach. They establish the motivations for the use of social media by teachers. Through the analysis of data collected through a questionnaire administered to 429 teachers, the authors learnt about the social networks they preferred to use for their learning, the differences in their use and the reasons they used these platforms for their teaching. Differences in means were contrasted considering the nominal variables of gender, age and educational level taught. Differences were found in the use of these social networks based on the gender and educational level at which teachers taught. Teachers said they felt motivated to use social networks owing to the opportunities for interaction and collaboration with other teachers and the advantages of obtaining resources and ideas to support their teaching.