The invention relates to a heating module for an exhaust gas system of an internal combustion engine, said heating module comprising at least one inlet opening and at least one outlet opening by means of which the heating module can be connected to the exhaust gas system, wherein a main line and a secondary line are provided between the inlet opening and the outlet opening to guide an exhaust gas flowing through the heating module, said main line and secondary line being in connection with one another at their upstream ends via a branching section and at their downstream ends via a merging chamber. A control device for controlling the exhaust gas flow flowing through the main line is further provided in the main line. The heating module is characterized in that the heating module comprises an oxidation catalyst that is at least sectionally arranged in the merging chamber. The invention further relates to a corresponding method.