Introduction: Socio-emotional competencies in face-to-face communication are an essential tool for personal and social adjustment from an early age. Online communication has become equally important, especially in adolescence. It is known that its characteristics require specific skills, but there is a lack of studies that analyse the relationship that exists between generally acquired socio-emotional skills and those necessary for online communication. Hence, this research is focused on analysing how offline socio-emotional skills predict these online competencies in girls and boys in a differentiated way. Method: This study included 478 Secondary Education students between 10 and 14 years of age. This is a cross-sectional study that used Path Analysis differentiated by sex, with intentional and non-probabilistic sampling. To assess socio-emotional competencies, we used the ESCQ-21 instrument for generally assessed socio-emotional competencies and the e-COM questionnaire to quantify online socio-emotional competencies. Results: The explanatory model indicates that socio-emotional competencies are partially transferred to the online environment in both sexes, especially Perception and comprehension. Furthermore, it is suggested that E-self-control of impulsiveness and E-emotional autonomy require specific development in that environment. Conclusions: It seems reasonable to include online experiences that encourage development in online spaces. The repercussions for the educational field are analysed.