A coil substrate includes a substrate, a coil-shaped wiring provided on one surface of the substrate, the coil-shaped wiring including adjacent parts provided adjacent to each other, and an insulating layer formed between the adjacent parts of the coil-shaped wiring. The coil-shaped wiring includes a first wiring, and a second wiring that is layered on the first wiring and has a thickness greater than a thickness of the first wiring. A space is provided between a side surface of the first wiring and the insulating layer. The second wiring fills the space and covers the first wiring. Both side surfaces of the second wiring contact the insulating layer.