A stack link fault response system includes a connected device, a first networking device, and a second networking device that is coupled to the connected device by first connected device link(s), and to the first networking device by stack links. The second networking device uses the stack links to transmit connected device communications received through the first connected device link(s) from the connected device. When the second networking device determines that a subset of the stack links are unavailable to transmit communications while at least one of the stack links is available to transmit communications, it performs a stack link fault response action that is configured to prevent the connected device from sending at least a portion of the connected device communications through the first connected device link(s) to the second networking device.