The teaching of social and emotional competencies (TSEC) is crucial for the academic and social development of learners of school age. The TSEC is more effective when it is carried out by teachers. This study aimed to analyse the relation between the teachers' characteristics and their TSEC. Participants were 731 secondary education teachers (55.7% females and 4.2% unreported gender; age: M = 44.6 years old, SD = 9.6, range 21-65) from 40 schools of Cordoba, a province of Spain. This ex-post-facto cross-sectional and multilevel study was conducted with self-reported surveys. Different teachers' characteristics were related to their TSEC, such as being female, having experience with students with special educational needs, having a higher level of social and emotional competencies, higher scores in the importance of promoting social and emotional competencies, higher level of planning the TSEC and working in public-private schools. These findings emphasise the importance of teachers' characteristics for the TSEC. Implications for teacher training and improved school practices are discussed.