A seat switch for a seat having a resilient web includes device for sensing the presence of an operator sitting on the resilient web. The seat switch is operably connected to a vehicle circuit which may be for example an ignition system for the engine. The seat switch provides a signal to the vehicle circuit in response to sensing no operator present. The device for sensing may include a switch and a tension member mounted directly to the web. When an operator sits on the seat, the web stretches under the weight of the operator, which results in tension in the tension member. This tension activates the switch to send the operator-present signal to the vehicle circuit. When the operator's weight is removed from the seat, the tension is relieved from the resilient web and the switch discontinues the operator-present signal.