Learn · Orders and fills
Limit orders and Market orders
The difference between setting a price boundary and immediately taking available liquidity.
Last updated: 2026-09-20
A limit is a boundary
A Limit order specifies a quantity and a price. A purchase can execute at that price or below; a sale can execute at that price or above. MockTradeCity uses a price tick of 0.01 CC. The limit describes an acceptable boundary, while the resting counterparty supplies each execution price. A purchase limited to 20.00 CC can therefore fill at 19.98 CC if an eligible Ask is waiting there.
A limit does not promise a fill. A bid below every eligible Ask has nobody to match immediately, and a sale above every eligible Bid faces the same problem. Depending on time in force, the remainder can wait or be canceled. Submitted limits also face the city's reference-price protection, currently a twenty percent boundary, and resting orders must satisfy the applicable price-band rules. A valid-looking number is not automatically an eligible order.
Market orders still have protection
A Market order asks the engine to match immediately against available eligible orders, beginning at the best opposite price. You enter quantity without choosing a limit. In the city, Market orders execute only during the Regular session and always use Immediate-or-cancel (IOC). They do not wait in the book after submission. If the market cannot supply the whole requested quantity, the unfilled portion is canceled rather than left pending.
The engine adds a protective price based on the reference price: up to 120 percent for purchases and down to 80 percent for sales. This restricts how far an order may reach through a thin book. The displayed reference amount is therefore not a guaranteed execution amount. A Market purchase reserves CC using its protection price, then releases excess funds as settlement and cancellation determine the amount actually needed. Price bands remain an additional constraint.
One request can have several outcomes
Suppose an eligible Ask offers 100 shares at 20.00 CC, followed by 100 at 20.10 CC. A 150-share Limit purchase at 20.00 CC can fill the first 100 and leave 50 unfinished. A Market purchase may reach the second level if all protections permit it, producing separate executions at different prices. Neither example promises that those quantities will still exist by the time a real request reaches the engine.
For a Day or Good till canceled (GTC) Limit order, a permitted remainder can stay open. For an IOC Limit order or Market order, it is canceled immediately. Partial execution is distinct from rejection: a rejected submission did not enter matching, while a partially filled order has actual trades that remain settled. Canceling an open remainder affects only that remainder. It cannot turn an already completed purchase or sale back into an untouched account.
Why an order may not execute
Price is only one condition. A company may be halted, the order's selected session may not be active, or available funds and shares may be insufficient. A Market order can encounter no eligible liquidity within its protective boundary. An accepted waiting limit can remain untouched even while trades print elsewhere, because those trades did not reach that limit under the required conditions. The ticket and order status distinguish these cases.
Stop Market and Stop Limit orders add a trigger before ordinary matching. Reaching the trigger makes the corresponding market or limit instruction eligible for processing; it does not guarantee its execution price or quantity. Funds, holdings and market state are checked again at activation. A Stop Market order remains subject to the Regular-session and immediate-execution restrictions. The trigger price therefore has a different role from the limit or protective price used during matching.
Where to compare orders in the city
The company ticket lists Limit, Market, Stop Market and Stop Limit types. Changing type updates the available inputs and explanations, including time in force and any automatic protection. For a Limit order, the estimated amount uses your selected price. For a Market order, the current reference amount describes the quote used for the estimate. The nearby Order book supplies context about quantities waiting at successive prices, without guaranteeing those quantities to an incoming request.
After submission, Account is the source for the accepted state, filled quantity and remaining quantity. Individual executions explain why the final consideration can differ from a preview or why an order has more than one fill. Open orders also explain reserved CC or shares. These are rules of MockTradeCity's fictional market, where every amount is City Coin. The Market rules page provides the current restrictions when a ticket's behavior needs a more precise explanation.