Stock Market Hours, Pre-Market, After-Hours, and the Move to 23-Hour Trading

The main US stock exchanges, the NYSE and Nasdaq, hold their regular trading session from 9:30 a.m. to 4:00 p.m. Eastern Time on weekdays, excluding market holidays. The Toronto Stock Exchange keeps the same regular hours. Outside those hours, US stocks can also trade in pre-market and after-hours sessions, and as of November 2026, US exchanges are scheduled to add an overnight session starting December 6, 2026, which would make most US stocks tradable about 23 hours a day, five days a week.

In short: regular hours are 9:30 a.m. to 4:00 p.m. ET in both the US and Canada. US exchanges also run extended sessions, generally from as early as 4:00 a.m. to 9:30 a.m. and from 4:00 p.m. to 8:00 p.m. ET. Extended-hours trading has less liquidity, wider spreads, and bigger price swings, and most brokers accept only limit orders then. The TSX has no comparable pre-market trading, only a pre-open order-entry period and a short after-close session at the closing price.

Regular sessions

Market	Regular session (ET)	Notes
NYSE	9:30 a.m. to 4:00 p.m.	Opening and closing auctions set the official open and close prices.
Nasdaq	9:30 a.m. to 4:00 p.m.	Opening and closing “crosses” set official prices.
TSX and TSX Venture	9:30 a.m. to 4:00 p.m.	Closing call 3:50 to 4:00 p.m.

Markets close on public holidays, which differ between the two countries. US markets close for Thanksgiving, for example, and Canadian markets close for Canada Day and Thanksgiving in October. Both publish annual holiday calendars, and both have occasional early closes; NYSE markets, for instance, close early at 1:00 p.m. ET on Friday, November 27, 2026, the day after US Thanksgiving.

Why the open and close matter

The opening and closing auctions collect orders and match them at a single price. A large share of each day’s volume trades at the close, because index funds and other institutions benchmark to closing prices. The first minutes after the open are often the most volatile and have the widest spreads, as overnight news and accumulated orders get priced in.

Extended hours in the US

Exchange	Pre-market	After-hours
Nasdaq	4:00 a.m. to 9:30 a.m. ET	4:00 p.m. to 8:00 p.m. ET
NYSE Arca	4:00 a.m. to 9:30 a.m. ET (Early session)	4:00 p.m. to 8:00 p.m. ET (Late session)

These are exchange hours. Your broker decides which of these hours you can actually trade in, and many offer narrower windows than the exchanges.

How extended-hours trading differs

Extended-hours orders are typically matched electronically without the auctions and without the full depth of the regular session. The SEC’s investor bulletin on extended-hours trading lists the main risks, and FINRA and exchange rules require brokers to disclose them before you can trade:

Lower liquidity. Fewer buyers and sellers. Some stocks don’t trade at all.
Higher volatility. Prices can swing more, and some volatility protections that apply in regular hours are limited or absent.
Changing prices. The extended-hours price may not reflect where the stock trades at the next open.
Unlinked markets. Different venues may show different prices at the same time.
Exaggerated effect of news. Earnings and other announcements often come out after the close or before the open, when liquidity is thinnest.
Wider spreads. Fewer quotes mean bigger gaps between bid and ask; see the bid-ask spread explained.

Most brokers accept only limit orders in extended hours. Orders marked “day” usually don’t carry into after-hours unless you specifically enable it. The details are in stock order types.

A worked example: trading on earnings after the close

Maple Widgets Inc. (a hypothetical company) closes at $50.00 with a typical regular-hours spread of $0.02. At 4:05 p.m. it reports earnings below expectations (the mechanics of these reports are covered in how earnings reports work). In the after-hours session the quote shows:

Bid: $44.10 for 100 shares
Ask: $45.40 for 100 shares

The spread is $1.30, about 2.9% of the midpoint, roughly 65 times the usual $0.02.

If you rush to sell 300 shares with a limit order at $43.50, you might fill only 100 shares at $44.10, then the next 200 at whatever lower bids appear, say $43.60. Average: about $43.77, a total of $13,130. If the stock opens the next morning at $46.00 as more buyers arrive, those 300 shares would have fetched $13,800 at the open. The after-hours sale cost about $670 compared with waiting. It could just as easily have gone the other way. The point is that thin markets produce prices that can differ sharply from where the stock trades once full liquidity returns.

The TSX outside regular hours

Canadian markets do not offer US-style pre-market trading on the TSX. According to TMX’s published schedule:

TSX and TSXV session	Time (ET)
Pre-open (orders entered, nothing trades)	7:00 a.m. to 9:30 a.m.
Opening	9:30 a.m.
Continuous trading	9:30 a.m. to 4:00 p.m.
Closing call	3:50 p.m. to 4:00 p.m.
Extended trading session (trades at the last sale price only)	4:15 p.m. to 5:00 p.m.

Canadian investors can still trade inter-listed stocks (companies listed in both Toronto and New York) in US extended hours through a broker that offers US trading, in US dollars.

Overnight trading and the move to 23 hours (as of November 2026)

Where things stood before

Before 2026, overnight trading in US stocks happened mostly on alternative trading systems (ATSs) that some retail brokers connected to. These venues showed the risks of thin overnight markets. On August 5, 2024, during a sharp global sell-off, the largest overnight venue, Blue Ocean ATS, hit its capacity limits; it cancelled all trades executed between 1:45 a.m. and 3:06 a.m. ET and halted that night’s session, and the brokers that used it had to suspend overnight trading.

What changed in 2026

Several pieces of infrastructure had to move together, and as of November 2026, most have:

Exchange approvals. On April 10, 2026, the SEC approved Nasdaq’s proposal to add a night session from 9:00 p.m. to 4:00 a.m. ET, alongside its existing 4:00 a.m. to 8:00 p.m. day session. NYSE Arca, Cboe EDGX, and other exchanges have filed or received approval for similar overnight sessions, and NYSE Arca’s plan grew from 22 hours to the same 23-hour framework.
Clearing. DTCC’s clearing subsidiary, NSCC, extended its operations to a 24x5 schedule on June 28, 2026, running from 8:00 p.m. ET Sunday to 8:00 p.m. ET Friday.
Consolidated data. The securities information processors (SIPs) that publish the national quote and trade data needed approval and system changes to operate overnight. Exchanges’ launch plans were made subject to SIP readiness.
Launch date. As of November 2026, Nasdaq and NYSE Arca are scheduled to open their first overnight session at 9:00 p.m. ET on Sunday, December 6, 2026. Trading would then run from Sunday 9:00 p.m. through Friday 8:00 p.m. ET, with a one-hour pause from 8:00 p.m. to 9:00 p.m. each weekday evening.

Because this launch is after this article’s publication date, check the exchanges’ notices for whether it happened on schedule. Some implementing rules were still awaiting SEC approval in the autumn of 2026.

How overnight trades will work

Trade date. Trades executed between 9:00 p.m. and midnight ET carry the next calendar day’s trade date. Trades between midnight and 4:00 a.m. carry that day’s date. Settlement remains T+1, counted from the trade date; see how a stock trade settles.
Access. Only exchange members can trade directly. Retail investors get access only if their broker chooses to offer the session, and brokers may restrict which orders and stocks they allow.
Safeguards. The exchanges’ plans include price protections for limit orders and temporary price bands in the overnight session. Overnight trades are reported with an extended-hours sale condition and don’t set the official last sale price.
No change for listed companies. Listed companies can’t opt out of having their shares trade overnight.

What hasn’t changed

The official open and close remain the 9:30 a.m. and 4:00 p.m. ET auctions, which set the prices used for index calculations and fund valuations.
Market-wide circuit breakers are measured against the S&P 500 during regular hours: a 7% or 13% fall halts trading for 15 minutes (if before 3:25 p.m.), and a 20% fall halts trading for the rest of the day.
Liquidity overnight is expected to be thin outside the first hour or so, so all the extended-hours risks above apply with more force.
As of November 2026, Canadian exchanges have not announced a comparable overnight session for TSX-listed stocks.

What can go wrong

Market orders in thin sessions. Most brokers block them in extended hours for good reason. Use limit orders.
Reacting to news at the worst moment. Earnings and global events often hit when liquidity is lowest, and the extended-hours price may not hold.
Venue or broker outages. The August 2024 cancellations showed that overnight infrastructure can fail under stress, and cancelled trades can leave you with a position you thought you had closed, or the reverse.
Stop orders that don’t work outside regular hours. Many brokers only trigger stops during the regular session, so an overnight drop can blow through your stop level before it activates.
Assuming 23-hour trading means 23 hours of fair prices. More hours doesn’t mean more buyers and sellers at 2 a.m.

The short version

US and Canadian stocks trade in regular sessions from 9:30 a.m. to 4:00 p.m. Eastern. US exchanges add pre-market and after-hours sessions from 4:00 a.m. to 8:00 p.m. ET, with thinner trading and wider spreads, and as of November 2026 an overnight session is scheduled to begin on December 6, 2026, bringing US stocks to about 23 hours a day. The TSX has no equivalent pre-market or overnight trading. Longer hours give more chances to trade, not better conditions for trading.