Abstract This study analyzes the state of mathematical competencies of pre-service teachers of the Complementary Training Program (CTP) of the Escuela Normal Superior Cristo Rey, from Barrancabermeja, Colombia and compares it with the results obtained in a private and an official university. The research has a quantitative, non-experimental, longitudinal approach, having as variable the mathematical knowledge of the students of the sample, from a comparative analysis of the levels of Mathematical Knowledge for Teaching (MKT) at the beginning -first semester- and at the end -fourth semester- of the educational process. The test measures three mathematical competencies: reasoning, communication and problem solving. The results show that in all samples there is low performance in the communicative competence and that students in the first semester of the public university show better competencies than those in the Complementary Training Program (CTP) and private university, in that order. However, at the end of the course, it is the CTP students who show better performance than their public and private university counterparts. This could be due to the emphasis on science and mathematics didactics, as well as the constant exposure to class planning and professional practices. In conclusion, students, future teachers, both in their first and last semesters, need to reinforce their communicative competence in mathematics and their exposure to professional practices should be privileged throughout their careers.