Market orders and limit orders: read the instructions before trading

AI-assisted Stockatlass editorial. Educational information, not investment advice. An order is an instruction to a broker. Understanding that instruction helps explain why the price on a screen and the price of a completed trade can differ. This article compares two common order types using the SEC's investor-education guidance. A market order seeks a purchase or sale at the best available price. It generally executes promptly, but its execution price is uncertain. The last recorded trade is not a promise about the next transaction. The SEC also notes that portions of a large market order can execute at different prices when insufficient shares are available at one price. A limit order puts a boundary on the acceptable price. A buy limit permits execution at that price or lower; a sell limit permits execution at that price or higher. That boundary does not guarantee a completed trade. An order can remain unfilled rather than execute outside its limit. Execution involves a process. Investor.gov explains that an online order goes to the broker, which routes it for execution. Prices can change while that happens. Seeing a quote and submitting an instruction therefore do not establish the final transaction price. Our suggested learning worksheet records the exact security, buy or sell instruction, order type, any price boundary, and the broker's explanation of how long the instruction remains active. Keep the submitted instruction separate from the eventual execution report. If a status message is unclear, record the uncertainty and request clarification. The SEC warns that available instructions and their implementation can differ between brokerage firms. These US educational sources do not establish every market's rules. Understanding an order's conditions is a reading exercise, not a recommendation to trade or a method that guarantees a profitable result. Sources checked: 2026-10-12 (Asia/Kolkata).