OCO (One-Cancels-Other)
A pair of orders linked so that when one fills, the other automatically cancels — the foundation of a bracket order.
OCO is an order-management primitive, not an order type. Two orders are submitted together with a link: when one executes (or partially executes), the other is cancelled (or reduced) in proportion.
In bracket trading, the stop and target form an OCO pair. If the target fills, the stop cancels. If the stop fills, the target cancels. Both fire at the broker, not chart-side — meaning they survive platform restarts and execute even if your charting software is offline.
Related terms
- Bracket order
A protective pair of orders — a stop loss and a profit target — attached to an entry as a one-cancels-other group.
- Limit order
An order to buy at a specified price or lower, or sell at a specified price or higher — only fills if the market reaches that price.
- Stop order
An order that becomes a market order once a trigger price is hit — most commonly used to limit losses on an open position.