Learn · How the city works
The four trading sessions
How the city's Eastern Time schedule affects activity, order eligibility and displayed price changes.
Last updated: 2026-09-20
One day, four periods
MockTradeCity uses Eastern Time for its trading schedule. Overnight runs from 8:00 p.m. to 4:00 a.m., Pre-market from 4:00 a.m. to 9:30 a.m., Regular from 9:30 a.m. to 4:00 p.m., and After-hours from 4:00 p.m. to 8:00 p.m. The periods meet without a scheduled gap. Overnight crosses midnight, but it remains one named session rather than restarting simply because the calendar date has changed.
The city follows this schedule seven days a week, including weekends. Its clock is a product rule for a fictional market, not a real exchange calendar. Eastern Time follows New York's daylight-saving changes, so the offset from your own location can change during the year. Session labels and the timing shown by the order ticket help connect your local day to the market's day without assuming one fixed UTC offset.
Activity changes with the clock
Virtual participants vary their pace across sessions. The beginning and end of Regular trading have more concentrated activity, while Overnight is generally quieter. Market makers also operate outside Regular hours, subject to inventory and risk constraints. This makes continuous trading possible without promising a constant amount of liquidity. An open market can still have a small quantity at its best Ask or no eligible counterparty for a particular order.
Depth is the quantity waiting at successive price levels. When depth is thin, an incoming order may reach several levels before completing, or stop with an unfilled remainder. A wider spread means the best Bid and Ask are farther apart. Neither condition changes price priority or time priority. They describe the orders available under the same matching rules at that moment, and can vary within a session as well as between sessions.
The session setting belongs to the order
The ticket separates execution session from time in force. The first defines when an order may match: Regular only, Regular plus extended hours, all sessions including Overnight, or Overnight only. The second defines how long an unfinished order may remain. A Good till canceled (GTC) Limit order can survive across days while becoming eligible only during its selected periods. Existing reservations remain commitments while that order is waiting for its session.
Day and GTC Limit orders can wait for a later eligible session. Immediate-or-cancel (IOC) orders cannot wait in that way: submitting outside their selected session is rejected. Market orders execute only during Regular hours and use IOC. For example, a Regular-only GTC Limit order entered in Pre-market can wait until Regular opens. That waiting state says nothing about whether its price will meet a counterparty once the session begins.
Closing prices and order deadlines
The Regular session provides the reference for the main daily price change. Previous close means the previous Regular session's closing price, not whichever trade happened immediately before your visit. Outside Regular hours, an additional session quote can show a different comparison against the Regular price. This creates two legitimate percentages on the same company page: the main daily move and the move in the labeled session use different reference points.
Day-order expiry also depends on the execution-session setting. Regular-only orders use a 4:00 p.m. Eastern deadline; Overnight-only orders use 4:00 a.m.; the other supported scopes use 8:00 p.m. An order entered exactly at a cutoff belongs to the next applicable window. Expiry cancels the remaining quantity and releases its reservation. It does not undo earlier fills, and it does not require you to be online when the deadline arrives.
Where to see sessions in the city
On a company page, the label beside an extended-session quote identifies whether you are reading Overnight, Pre-market or After-hours data. The Order book and recent trade list show the current pace directly. Watching those together separates a quiet market from a ticket that is simply waiting for its permitted session. The main quote and the additional session quote answer different questions, so their reference prices matter as much as their displayed colors.
In the order ticket, changing execution session updates the timing explanation. Account then shows the resulting order state, including an order waiting for a session to begin. Its remaining quantity and expiry explain whether funds are still committed. Market rules contains the published schedule. When tracing an order, matching its session, time in force and price against the current book usually supplies more information than the current time alone can provide.