Provided is an outdoor unit for an air conditioner and the like that provide notification of whether maintenance is needed for an outdoor heat exchange unit in appropriate timing. The outdoor unit for the air conditioner includes: a compressor; an outdoor heat exchange unit through which a refrigerant flows by driving of the compressor; an outdoor fan that includes an outdoor fan motor and is installed near the outdoor heat exchange unit; and a control unit that provides notification of whether maintenance is needed for the outdoor heat exchange unit based on an airflow resistance during an outdoor air-sending operation in which the outdoor fan is driven to send outdoor air into the outdoor heat exchange unit while the compressor is stopped. This makes it possible to provide the notification of whether the maintenance is needed for the outdoor heat exchange unit in appropriate timing.