According to Education Portal, it takes a minimum of 12 years to become a cardiologist. A prospective cardiologist's training can take much longer, depending on the length of time spent in undergraduate studies, medical school, residency programs and fellowship programs.
Education Portal notes that residency programs finished after medical school typically last two to six years. If someone who wants to be a cardiologist took four years of undergraduate education, four years of medical school, six years of residency and three years of training in a fellowship program, it would take him 17 years to complete all training. It is important to note, however, that postgraduate training completed after medical school is typically paid.