Example embodiment non-volatile memory devices may be capable of increased integration and reliability and may provide example methods of operating non-volatile memory devices. Example embodiment non-volatile memory devices may include a first control gate electrode on a semiconductor substrate. A first charge storing layer may be between the semiconductor substrate and the first control gate electrode. A source region may be defined in the semiconductor substrate at one side of the first control gate electrode. A first auxiliary gate electrode may be at the other side of the first control gate electrode and may be recessed into the semiconductor substrate. A first drain region may be defined in the semiconductor substrate at one side of the first auxiliary gate electrode opposite to the first control gate electrode. A bit line may be connected to the first drain region.