A vehicular heating control system, method, and program acquire an operation value that is a setting by an occupant and, when there is no manual operation, acquire a fuel consumption reduction amount and a fuel consumption amount and, when the fuel consumption reduction amount exceeds the fuel consumption amount and an improvement in fuel economy is expected, execute seat heater control, that is, heating by an electrothermal heater, decrease the wind force of a blower fan, and lower an engine startup threshold value. Heating by an air conditioning system and heating by the electrothermal heater are combined, so a heating effect is obtained while reducing the fuel consumption amount.