A clutch device is comprised of: an end wall rotatable about an axis; an extended wall elongated as a unitary body from a first face of the end wall along the axis to define a circular slot; a clutch including a clutch member movable along the axis and capable of resting on a second face of the end wall; and a solenoid configured to drive the clutch member along the axis, the solenoid including a core conducting a magnetic flux, the core including a fitting portion slidably fitting in the circular slot, an abutment portion projecting radially outward from the fitting portion to abut along the axis on the extended wall, and a back portion projecting outward along the axis from the circular slot and retracting radially inward from the contact portion.