A coil component includes a drum core including a winding core portion and a flange portion disposed on an end portion thereof the winding core portion in its axial direction, a planar core having a lower principal surface, and a wire wound around the winding core portion. The flange portion includes an inner end surface, an outer end surface, a bottom surface, and a top surface. The inner end surface positions the end portion of the winding core portion. The bottom surface links the inner end surface and the outer end surface and placed so as to face a mounting substrate side when being mounted. The lower principal surface of the planar core is fixed to the top surface with an adhesive interposed therebetween. The top surface includes a protrusion with a vertex positioned closer to the inner end surface than to the outer end surface.