The invention relates to an atomizer for an electronic smoking device, to a cartomizer with an atomizer and to an electronic smoking device with an atomizer. In order to improve atomizing efficiency, the atomizer comprises a heating coil made of a heating wire with a first section and a second section, wherein the first section comprises an electrical resistance per length unit that differs from an electrical resistance per length unit of the second section, and wherein the heating coil has a first winding, a last winding and at least one inner winding between the first winding and the last winding, wherein the at least one inner winding comprises the first section, the first winding comprises the second section, and the last winding ROM comprises a third section, wherein the electrical resistance per length unit of the third section corresponds to the electrical resistance per length unit of the second section.