What Is a Bracket Order and How Does One-Cancels-Other Work?

What happens to the stop when the target fills? In a bracket order, the platform cancels it for you. That link between the two exits is called one-cancels-other, or OCO, and it’s the reason brackets exist.

A bracket has three legs. The entry is usually a limit order. Attached to it are two exits that wait until the entry fills: a sell limit above the price to take profit and a sell stop below it to cap the loss (flip both for a short). Once the entry fills, both exits go live together. Whichever one executes first cancels the other.

Why traders use them

The exit plan exists before the trade does.

That sounds minor until you look at what it removes. The usual gap in a discretionary trade is the stretch, minutes or sometimes hours, between getting filled and getting around to placing a stop, and a bracket closes it; it also takes away the urge to rethink the target while the position is open and the price is moving, which is when judgment tends to be at its worst. With the bracket working, an alert on the stock becomes a reason to check whether the plan still holds, the approach argued in treating a price alert as a prompt to check your plan.

The catch is that a bracket knows two prices and nothing else. If the reason for the trade falls apart halfway between the stop and the target, say because a news item lands that changes the picture for the company, the bracket will keep waiting for one of its two levels, and closing the position early means canceling the group and exiting yourself. Some traders add a time rule on top, such as being out by the close.

A worked bracket in R

R is the amount you stand to lose if the stop is hit. Measuring the target in multiples of R lets you compare trades of different sizes and prices.

The stop leg is normally a stop market order, so the 300 is planned risk. Slippage or a gap can make it larger. The trade risk worksheet runs the same sums for your own entry, stop and size.

Pitfalls

Partial fills cause the most confusion. Say only 200 of the 500 shares fill at 25.00. Some brokers size both exits to the 200 you actually hold and adjust them as more fills arrive. Others behave differently, and a few may leave exits sized to the full order, so check how yours handles it before the first real trade, and see what happens when an order partially fills for the general mechanics.

Editing one leg is the next trap. Moving the stop up is a normal thing to want. On some platforms that edit keeps the OCO link intact. On others it can cancel and replace the whole group, or break the link so the two exits are no longer tied, and that’s how a trader ends up with a filled target and a stop still working on a position that no longer exists. Read the platform’s rules on editing brackets.

The legs can also carry different time in force settings. A day entry with GTC exits is common. A day stop leg that expires at the close leaves the position with only a target overnight.

Extended hours are a gray area. Many platforms accept brackets only for the regular session, or let the limit legs work in extended hours while the stop leg does not. Brokers vary.

And a bracket won’t save you from a gap. It’s still made of ordinary orders, so a gap below the stop fills the stop leg at the open, wherever that is.

Some platforms let the stop leg be a trailing stop, which keeps the OCO link while the protective price follows the stock upward.