Stop limit order: what it is, how it works, and when to use one

A stop limit order is a type of conditional order that activates when a security reaches a specified stop price and then converts into a limit order at a specified limit price.

When placing the order, the investor selects both prices:

• Stop price: The price that activates the order.

• Limit price: The least favourable price at which the order may execute.

• Gap between stop and limit: The amount of price movement accepted between activation and execution.

For a sell order, the limit price establishes a minimum acceptable selling price. For a buy order, the limit price establishes a maximum acceptable purchase price.

The key feature of a stop limit order is that it separates the trigger from the execution price. Once the stop price is reached, the order becomes active as a limit order.

For example, a sell stop limit order may attempt to sell shares at the limit price or higher after the stop price is reached. If no buyer is available at that price, the order may remain unfilled.

This characteristic distinguishes stop limit orders from some other order types because execution depends not only on the trigger being reached, but also on the availability of a matching trade at the specified limit price.

How a stop limit order works: the two-price mechanism

The mechanics of a stop limit order can be broken into several steps.

Step 1: set the stop price and limit price

When entering the order, the investor chooses:

• A stop price

• A limit price

• An order duration, such as a day order or order duration good till cancelled (GTC)

Step 2: the order waits for the trigger

Before activation, the stop limit order remains inactive. It waits for the security to trade at or through the stop price.

Step 3: the stop price is reached

Once the security trades at the stop price, the order is activated.

This event is often described as a stop limit order triggered.

Step 4: the order becomes a limit order

After activation, the order converts into a standard limit order using the previously specified limit price.

Step 5: execution is attempted

The order then attempts to execute:

• At the limit price

• Or at a more favourable price

If a matching counterparty is available, execution may occur.

If not, the order remains open until:

• It executes

• It expires

• It is cancelled

An important detail is that stop orders are generally triggered using the last traded price rather than the bid or ask price.

Although a stop limit order may help establish execution boundaries, it does not guarantee execution at or near the stop price. The order only establishes the acceptable execution range after activation.

Sell stop limit orders: protecting a position

A sell stop limit order is often associated with attempts to limit downside exposure while maintaining control over the execution price.

Illustrative example only

Suppose an investor owns 100 shares of a company currently trading at $50.

The investor enters:

• Stop price: $45

• Limit price: $44.50

Scenario A: orderly price decline

The stock price gradually declines to $45.

Once the stop price is reached:

• The order activates.

• It becomes a sell limit order at $44.50.

• Buyers are available at $44.75.

The order executes at $44.75, which is above the limit price.

Scenario B: gap through event

Assume the company releases negative news after the market closes.

The next trading day, the stock opens at $42.

The stop price is triggered because trading occurs below $45. However, the limit order requires execution at $44.50 or better.

Because the stock is trading at $42 and no buyers are available at $44.50 or higher, the order remains unfilled.

The investor continues holding the shares while the current market price remains below the limit.

Important risk consideration

A sell stop limit order does not guarantee an exit from a position.

If the market moves below the limit price before a trade occurs at that level, the order may not execute. In these situations, losses may exceed the level the investor originally intended to address.

This possibility is sometimes referred to as a non-execution risk stop limit.

Buy stop limit orders: entering on a breakout

A buy stop limit order may be used when an investor wants to enter a position only after a security reaches a specified price level.

Illustrative example only

Assume a stock is trading at $30.

The investor wishes to automatically trigger a buy order only if the stock price reaches $35 .

The investor places:

• Stop price: $35

• Limit price: $35.50

If the stock reaches $35:

• The stop activates.

• The order converts to a buy limit order.

• The order seeks execution at $35.50 or lower.

Now assume strong buying activity pushes the stock directly to $37.

Because the limit price is $35.50, no shares are available within the acceptable range.

The order remains unfilled.

In this situation, the investor avoids purchasing above the selected limit price but does not participate in the move.

A buy stop limit order may be considered when:

• The investor wants confirmation of upward price movement.

• The investor wants to establish a maximum entry price.

• The investor accepts the possibility that the order may not execute.

Because of this use case, some investors view the buy stop limit order as a type of breakout order type.

The gap-through risk: when a stop limit order may not execute

One of the most important concepts associated with stop limit orders is gap through risk.

This occurs when a security moves directly through the limit price without trading at it.

Several situations may contribute to this outcome:

• Company announcements released outside regular trading hours

• Significant market-wide events

• Low-liquidity securities with wide price intervals between trades

In these scenarios, the stop price may be triggered, causing the order to become a limit order.

However, if the next available trade occurs:

• Below the limit price for a sell order

• Above the limit price for a buy order

The order remains unfilled.

The position stays open because the conditions for execution have not been met.

The importance of the stop limit gap

The difference between the stop price vs limit price can influence how the order behaves.

A wider gap may increase the likelihood that a matching trade becomes available.

A narrower gap may increase price control but could also increase the likelihood of an order not executed during a rapid move.

Neither approach guarantees execution.

The appropriate distance between the stop and limit prices may vary based on factors such as:

• Security liquidity

• Typical trading range

• Volatility

A stop limit order does not protect against loss if the order fails to execute. During a significant gap move, both the stop trigger and the limit price may be passed before any trade occurs, leaving the position open.

Stop limit order vs stop market order

The comparison between a stop limit vs stop loss or stop market order is one of the most common areas of confusion among investors.

Both orders use a stop price as a trigger, but they behave differently after activation.

Stop market order

When triggered, a stop market order becomes a market order.

The order seeks execution at the next available market price.

Characteristics include:

• Higher likelihood of execution

• Less control over execution price

• Potential exposure to slippage stop order effects during fast-moving markets

The actual executed price investing outcomes may differ significantly from the stop price.

Stop limit order

When triggered, a stop limit order becomes a limit order.

Characteristics include:

• Greater control over execution price

• Potentially lower likelihood of execution

• Exposure to non-execution risk stop limit

Comparison table

Stop limit order vs limit order

Understanding stop limit vs limit order begins with understanding when each order becomes active.

A standard limit order enters the market immediately after submission. It remains active at the specified price and waits for a matching trade.

A stop limit order works differently. It remains inactive until the stop price is reached. Only after activation does it become a limit order.

For example:

• A sell limit order may be immediately eligible for execution if the market is already trading at or above the limit price.

• A sell stop limit order remains dormant until the security first declines to the stop price.

This distinction makes stop limit orders a form of conditional order rather than a continuously active order.

A note for Canadian investors: TSX order types

For many Canadian-listed equities, a TSX stop limit order may be the primary stop triggered order available through a brokerage platform.

Important considerations include:

• Stop limit orders are commonly available for eligible TSX-listed securities.

• Stop market orders may not be available for many Canadian-listed equities.

• Availability can vary by brokerage and security.

• Stop orders are generally triggered using the last traded price.

• Stop orders generally cannot be combined with all-or-none qualifiers.

Canadian investor note

A Canadian investor considering a stop triggered order may wish to confirm order-type availability, security eligibility, and platform-specific requirements before placing a conditional order.

Brokerage platforms may apply different rules depending on the market and security involved.

Order duration: day orders vs good till cancelled

When placing a stop limit order, investors typically choose an order duration.

Day order

A day order investing instruction remains active only for the current trading session.

If the order is not triggered or executed before the market closes, it expires automatically.

Good till cancelled order

A good till cancelled order remains active until:

• It executes

• It is cancelled

• It reaches the platform's maximum permitted duration

This duration is often referred to as order duration GTC.

For stop limit orders, investors may also wish to understand:

• Whether the order remains active overnight

• Whether after-hours trading can trigger the stop

• Whether platform-specific limitations apply

These details can vary between brokerages and markets.

Common misconceptions about stop limit orders

Misconception 1: "my stop price is the price I'll sell at"

The stop price is a trigger, not an execution price.

After activation, the order becomes a limit order. Execution may occur at the limit price or better, or the order may remain unfilled.

Misconception 2: "a stop limit order will always protect me from large losses"

A stop limit order may not execute if the market moves through the limit price.

When this occurs, the position remains open.

Misconception 3: "a stop limit and a stop loss are the same"

The term stop loss order is often used broadly to describe stop triggered orders intended to limit losses.

A stop limit order is one specific type of stop triggered order. A stop market order is another. Their execution mechanics differ.

Final thoughts on stop limit orders

A stop limit order is a conditional order that combines a stop price and a limit price to establish both a trigger point and an acceptable execution range. Once the stop price is reached, the order becomes a limit order and may execute only at the limit price or better. While this order type can provide greater control over the execution price, it also introduces the possibility that the order remains unfilled during rapid market movements. Understanding how stop limit orders work, including gap-through risk, order duration, and differences from other order types, can help investors make more informed decisions when placing trades.