An inductor component comprising a single-layer glass plate of a rectangular parallelepiped shape with a width, a length longer than the width, and a height, and having a bottom surface defined by the length and width and a top surface positioned on a back side of the bottom surface; bottom-surface and top-surface conductors disposed above the bottom and top surfaces, respectively; through wirings each extending through a corresponding one of through holes formed in the glass plate; an underlying insulation layer above the bottom-surface conductors; and first and second terminal electrodes above the underlying insulation layer. The bottom-surface and top-surface conductors, and the through wirings are electrically connected as a circularly extending wiring that circularly extends around a winding axis parallel to the bottom surface and the length. The circularly extending wiring, and the first and second terminal electrodes, are electrically connected to each other as an inductor element.