A one-cancels-the-other order (OCO) is a pair of orders stipulating that if one order executes, then the opposite order is mechanically canceled. An OCO order combines a forestall order with a restrict order on an automatic trading platform. When both the prevent or restrict fee is reached and the order executed, the opposite order mechanically gets canceled. Experienced buyers use OCO orders to mitigate risk and to enter the marketplace.For instance, if a inventory is buying and selling in a range among $20 and $22, a trader could area an OCO order with a purchase prevent simply above $22 and a promote prevent simply beneath $20. Once the fee breaks above resistance or beneath help, a change is performed and the corresponding forestall order is canceled. Conversely, if a dealer wanted to apply a retracement strategy that buys at support and sells at resistance, they could area an OCO order with a purchase restriction order at $20 and a sell restriction order at $22.