Primary cutaneous lymphomas are a group of T- (CTCL) and B-cell (CBCL) malignancies. These diseases have different clinical presentations and prognosis. Our knowledge on their epidemiology is limited. Aim of this review was to summarize recent findings on the incidence of CTCL and CBCL, how they change over time, and to describe possible causes and consequences. We found that although there are important differences in the epidemiology of cutaneous lymphomas in different countries, the relative frequency of certain, especially rare lymphomas remains stable. Several studies described growing incidences of both CTCL and CBCL. The emergence of new diagnostic criteria, a more precise definition of the entities and new biomarkers enable a better classification of cases.