A washing machine overflow prevention device for preventing flooding includes a plug-port assembly that comprises a plug, a port, and a breaker. The plug is configured to insert into an outlet that is coupled to an electrical circuit of a building. The port is configured to insert a power cord plug of a washing machine to power the washing machine, and the breaker is positioned to operationally couple the plug to the port. A switching sensor is coupled to and positioned in a standpipe. The switching sensor is operationally coupled to the plug and the breaker. The switching sensor is configured to detect a water level in the standpipe and to selectively actuate the breaker to decouple the port from the plug in event of a high-water level in the standpipe to prevent flooding of an area proximate to the washing machine.