Types of Orders

An order is an instruction from a customer to a broker-dealer to buy or sell a security under specified conditions. Orders vary by price control, time duration, and discretion.


Core Order Types

Order TypeHow It WorksExecutionKey Risk
Market orderBuy or sell immediately at the best available priceImmediate; fills as soon as it reaches the marketPrice uncertainty: you get speed but no price control
Limit orderBuy or sell only at a specified price or betterOnly when the market reaches the limit price (or better)May never execute if the price is not reached
Stop order (stop-loss)Becomes a market order once a specified stop price is triggeredAfter the stop price is hit, executes at the next available priceExecution price may differ significantly from the stop price
Stop-limit orderBecomes a limit order once the stop price is triggeredAfter the stop price is hit, only at the limit price or betterMay not execute at all if the price moves past the limit

Think of it this way:

  • Market order = "Execute now, whatever the price"
  • Limit order = "Execute only at my price or better"
  • Stop order = "If the price hits X, execute at the market"
  • Stop-limit order = "If the price hits X, execute only at Y or better"

Where to Set Limit and Stop Prices

This is one of the most commonly tested concepts. The placement of the trigger price depends on whether you are buying or selling:

OrderPlacement Relative to Current Market PriceWhy
Buy limitBelow current market priceYou want to buy at a lower price
Sell limitAbove current market priceYou want to sell at a higher price
Buy stopAbove current market priceTriggers a buy if the price rises (used by short sellers to limit losses)
Sell stopBelow current market priceTriggers a sell if the price falls (classic stop-loss protection)

Exam Tip: Gotchas

  • A stop order does NOT guarantee a specific execution price. Once triggered, it becomes a market order and fills at the next available price, which could be far from the stop price in a fast-moving market. A stop-limit order adds price protection but risks not executing at all.
  • Buy limits go below the market; sell limits go above. Students often reverse this. Think: you want to buy cheaper (below) and sell higher (above).

Time-in-Force Designations

Every order has a duration: how long it stays active if not executed.

DesignationMeaningPartial Fills?
Day orderExpires at the end of the trading day if not executed (this is the default)Yes
Good-til-canceled (GTC)Remains open until executed or canceled by the customerYes
Immediate-or-cancel (IOC)Must execute immediately; any unfilled portion is canceledYes (partial fills allowed)
Fill-or-kill (FOK)Must execute in its entirety immediately or the entire order is canceledNo (all or nothing, right now)
All-or-none (AON)Must execute in its entirety, but does NOT need to fill immediatelyNo (all or nothing, but can wait)

The key distinctions:

  • IOC vs. FOK: Both require immediate action, but IOC allows partial fills while FOK does not
  • FOK vs. AON: Both require the full quantity, but FOK must fill immediately while AON can wait for liquidity
  • Day order: The default if no time-in-force is specified

Exam Tip: Gotchas

  • If no time-in-force is specified, the order is a day order by default. It expires at the close of trading that day.
  • FOK and AON both require full fills, but only FOK must be immediate. AON can wait for liquidity to accumulate.