A spindle motor and a disk drive apparatus include a base member, an armature positioned above the base member, and a circuit substrate electrically connected to coils of the armature. The base member includes a bottom portion positioned below the armature and a lower slant surface extending radially outward and upward from an outer peripheral portion of a lower surface of the bottom portion. The circuit substrate includes a plurality of land portions arranged on its lower surface. The lower slant surface includes a first slant surface and a second slant surface arranged along a circumferential direction. At least one land portion is respectively arranged on each of the first slant surface and the second slant surface.